10 second questions

Jai Ganesh · 2008-12-11 01:43:51

Differentiate the following with respect to x.

#876.

#877.

#878.

#879.

#880.

Jai Ganesh · 2008-12-11 16:59:49

#881. The average of ten numbers is 7. What would the average of the new set of numbers be if each number is multiplied by 12?

#882. When 0.36 is written in the simplest fraction form, what is the sum of the numerator and the denominator?

#883. What is the difference between the biggest and the smallest fraction among

?

#884. What is the value of

?

#885. What is the value of

?

Jai Ganesh · 2008-12-12 02:37:39

#886. Two trains 140 meters and 160 meters long run at the speed of 60 kilometers/hour and 40 kiloeters/hour respectively in opposite direction on parallel tracks. What is the time in seconds they take to cross each other?

#887. Two trains of equal length are running on parallel lines in the same direction at 46 kilometers/hour and 36 kilometers/hour. The faster train passes the slower train in 36 seconds. What is the length of each train?

#888.A 270 meters long train running at the speed of 120 kilometers per hour crosses another train running in the opposite direction at the speed of 80 kilometers per hour in 9 seconds. What is the length of the other train?

#889. Two trains are running in the opposite direction with the same speed. If the length of each train is 120 meters and they crosseach other in 12 seconds, what is the speed of each train in kilometers/hour?

#890.A train overtakes two persons who are walking in the same direction in which the train is moving, at the rate of 2 kilometers/hour and 4 kilometers/hourand passes them completely in 9 and 10 seconds respectively. What is the length of the train?

JohnnyReinB · 2008-12-12 03:22:48

Ei Ganesh! Long time no post, hehe.

It's been a while. Ah well, too tired now to look at the others. Might explain any mistakes, too.

Jai Ganesh · 2008-12-12 18:49:14

Hi JohnnyReinB,
Indeed, you are tired!
I have never seen you make this many mistakes earlier.
Answers to #845 and #849 are correct.
Answer to #846 is 89 [(12x7)=5 = 89, (16x5)+9 = 89].
Answer to #848 is 1689. The answer you have given, 2520, is divisible by all the numbers 5,6,7,8, and 9.
Answer to #850 is 1088. which leaves a remainder of 8 when divided by 12, 15, 20, and 54.

Jai Ganesh · 2008-12-12 19:16:12

#891. One of the diagonals of a rhombus is double the other diagonal. Its area is 25 sqare centimeters. What is the sum of the diagonals?

#892. The two parallel sides of a trapezium are 1.5 meters and 2.5 meters respectively. What is the area of the trapezium if the perpendicular distance between them is 6.5 meters?

#893. The cross-section of a canal is trapezium in shape. The canal is 12 meters wide at the top and 8 meters wide at the bottom. If the area of cross section is 840 square meters, what is the depth of the canal?

#894. A man runs round a circular field of radius 50 meters at the speed of 12 kilometers per hour. What is the time taken by the man to complete twenty rounds of the field?

#895. What is the circumference of a circle whose area is 24.64 square meters?

JohnnyReinB · 2008-12-12 21:33:10

Ooh, sorry about that. Won't happen again, I hope:D

Jai Ganesh · 2008-12-13 01:09:37

Answers to #881, #882, #892, #893, and #894:-
The first four solutions are all correct. Very well done!
Regarding

Jai Ganesh · 2008-12-13 01:18:08

#896. The length of a rectangular plot is 60% more than its breadth. If the difference between the length and breadth of the rectangles is 24 centimeters, what is the area of the rectangle?

#897. The breadth of a rectangular field is 60% of its length. If the perimeter of the field is 800 meters, what is the area of the field?

#898. The diagonal of a rectangle is √(41) centimeters and its area is 20 square centimeters. What is the perimter of the rectangle?

Jai Ganesh · 2008-12-13 17:40:54

#899. A number is increased by 20% and then again by 20%. By what percent should the number be reduced so as to get back to the original number?

#900. If the price of petrol is increased by 30%, by how much percent should a car ownner reduce the consumption in order to maintain the same budget?

#901. The price of a shirt is increased by 15% and then rduced by 15%. What is the finap price of the shirt in terms of percentage increase/decrease over the original price?

#902. A number is decreased by 10% and then increased by 10%. The number so obtained is 10 less than the original number. What was the original number?

#903. Peter could save 10% of his income. But wo years later, when his income is increased by 20%, he could save only the same amount as before. By how much percent has his expenditure increased?

JohnnyReinB · 2008-12-14 00:39:26

Jai Ganesh · 2008-12-14 02:04:06

Answers to #896, #897, #898, #899, #900, #901, #902, and #903:-
JohnnyReinB,
Answers to #898, #900, #901, and #902 are correct!
50% score isn't bad, but by your standards, I expect you to score 100% correct, nothing less.

Jai Ganesh · 2008-12-14 02:19:07

#904. a train travels at an average of 50 miles per hour for 2½ hours and then travels at a speed of 70 miles per hour for 1½ hours. How far did the train travel in the entire four hours?

#905. A train runs at a speed of 108 kilometers per hour. What is its speed in meters per second?

#906. A man sitting in a train which is travelling at 50 kilometers/hour observes that a goods train, travelling in the opposite direction, takes 9 seconds to pass him.If the goods train is 280 meters long, find the speed of the goods train.

#907. How long does a train 110 meters long running at 72 kilometers/hour takes to cross a bridge 132 meters in length?

#908. A train running at the speed of 60 kilometers/hour crosses a pole in 9 seconds. What is the length of the train?

Jai Ganesh · 2008-12-14 16:59:56

#909. A solid sphere of total surface area 24 square centimeters is bisceted into two hemispheres. What is the total surface area of any one of the hemisspheres?

#910. The internal and external diameters of a hollow cylinder are 24 centimeters and 28 centimeters respectively. What is the thichness of the material?

#911. If the remainder when a - 2x + 5x² is divided by (x-2) is 7, then what is the value of a?

#912. If the ratio of the area of two squares is 225:256, then what is the ratio of their perimeters?

#913. Find the values of k for which 12x² + 4x + 3 = 0 has real and equal roots.

Jai Ganesh · 2008-12-15 02:48:26

#914. What is the value of n if

?

#915. The number obtained by interchanging the two digits of a two-digit number is less than the original number by 27. If the difference between the two digits of the number is 3, how many such numbers exist?

#916. A train running at the speed of 20 meters/second crosses a pole in 24 seconds less than the time it requires to cross a platform thrice its length at the same speed. What is the length of the train?

#917. Find the value of

.

#918. Find the value of

.

#919. Simplify:

.

#920. Find the value of 315375 x 999.

Jai Ganesh · 2008-12-15 17:42:54

#921. A, B, and C started a business by investing $120,000, $135,000 and $150,000 respectively. Find the share of each, if an annual profit of $56,700/- was earned.

#922. Alfred started a business investing $45,000. After 3 months, Peter joined him with a capital of $60,000. After another 6 months, Ronald joined them with a capital of #90,000. At the end of the year, they made a profit of #16,500. Find the share of each.

#923. Peter bought an item at 20% discount. He sold it with 40% increase on the price he bought it. By what percent is the new sale price more than the original price?

Jai Ganesh · 2008-12-16 01:06:34

#924. In what ratio must a grocer mix two vrieties of pulses cosing $15 and $20 per kilogram respectively so as to get a mixture worth 16.50 per kilogram?

#925. In what ratio must water be mixed with milk to gain 16 2/3 % on selling the mixture at cost price?

#926. Two vessels A and B contain spirit and water in the ratio 5:2 and 7:6 respectively. Find the ratio in which these mixtures are to be mixed to obtain a new mixture in vessel C containing spirit and water in the ratio 8:5?

#927.A vessel is filled with liquid, 3 parts of which are water and 5 parts syrup. How much of the mixture must be drawn off and replaced with water so that the mixture may be half watwer and half syrup?

JohnnyReinB · 2008-12-16 01:18:18

Jai Ganesh · 2008-12-16 03:43:58

Answer to #919:
JohnnyReinB, are you sure?

Jai Ganesh · 2008-12-16 03:50:13

#928. The line joining (-2,4) and (3,-5) is parallel to the line joining (0,4) and (-5,y). Find y.

#929. Write down the equation of the line perpendicular to 3x+8y=12 and passing through the point (-1,-2).

#930.A (2,4), B (0,4) and C (-6,0) are the given points. Find the slope of the line passing through B and the midpoint of AC.

Jai Ganesh · 2008-12-16 23:51:41

#931. If 729, x, 9 are in Geometric Progression, what is the value of x?

#932. For any two sets A and B, A - B is equal to.....
(1)

(2)
(3) (4) None of these

#933.When f(x) is divided by ax+b, what is the remainder?

#934. What are the nature of the roots of the equation x² - 4x + 4 = 0?

#935. What is the quadratic equation whose roots are 3 and 4?

#936. Find the sum of the first ten terms of an Arithmetic Progression whose nth term is
3n+2.

#937. Find the Greatest Common divisor of 2(x²-1), 3(x³-1), 4(x²-5x+4)

#938. Find the Geometric progression whose 5th term and 7th term are

respectively. Also find which term is
.

#939. Solve the quadratic equation:

.

#940. If

and
,
show that g(x) is a factor of f(x).

Jai Ganesh · 2008-12-17 16:29:58

#941. Find the intercepts made by the striaght line 3x-2y-6=0 on the axes of the co-ordinates.

#942. The midpoint of segment PQ is (5,1). If P is (8,4), find the point Q.

#943. An integer is chosen at random from 1 to 50 (both numbers included). Find the probability that it is a multiple of 7.

#944.If the seventh term of an Arithmetic Progression is 45 and the ninth term is 57, find the first term and the common difference.

#945. A solid metal cylinder is 20 centimeters in height and has a radius of 1.5 centimeters. It is melted down and cast into spheres of 1.5 centimeters radius each. How many such spheres can be formed from the cylinder?

Jai Ganesh · 2008-12-18 02:22:34

#946. If A = {2,4,6,8}, B = {1,2,3,4}, and U = {1,2,3,4,5,6,7,8,9,10}, then find A'-B'.

#947. The difference between Simple and Compound Interest on a sum of money lent at 8% per annum for 2 years is $12. Find the sum lent.

#948. If the polynomials ax³ + 4x² + 3x - 4 and x³ - 4x + a leave the same remainder when divided by (x-3), find the value of a.

#949. If x²-x-6 = (x+2)(x-p), find 'p'.

#950. If A = {3,4,5,6}, B = {2,5,6,7}, C = {1,3,6,7}, Verify

.

Jai Ganesh · 2008-12-19 01:16:45

#951. Find the compound interest on #6250 at 16% per annum for two years, compounded annually.

#952. The product of two numbers is 9375 and when the larger number is divided by the smaller one, the quotient is 15. What is the sum of the numbers?

#953. father can do a job as fast as his two sons working together. If one sons does the job in 3 hours and the other in 6 hours, how many hours would it take for the father to do the job?

#954.What is the value of

?

#955. If the cost of 12 pens is equal to the selling price of 8 pens, what is the profit percentage?

#956. A boat goes 40 kilometers upstream in 8 hours and 36 kilometers downstream in 6 hours. What is the speed of the boat in still water in kilometers/hour?

#957. Walking at the rate of 4 kilometers per hour, a man covers a certain distance in 2 hours and 45 minutes. Running at 16.5 kilometers per hour, in what time would the man cover the same distance?

#958. What is the value of

?

#959. Bananas are bought at the rate of 6 for $5 and sold at the rate of 5 for $6. What is the profit percentage?

#960. The average age of 12 students in a class is 20 years. If the age of one more student is included, the average decreases by 1. What is the vage of the new student?

Jai Ganesh · 2008-12-19 17:20:37

#961. After measuring 120 meters of a rope, it was discovered that the measuring rod was three centimeters longer. What is the true length of the rope measured?

#962. The sum and produce of two numbers are 12 and 35 repectively.What is the sum of their reciprocals?

#963. In a school having a total strength of 286 students, the rato of boys to girls is 8:5. If 22 more girls get admitted into the school, what would the new ratio of boys to girls be?

#964. Three numbers which are co-prime to one another aare such that the product of the first two is 551 and the product of the last two is 1073. What is the sum of the three numbers?

#965. The sum of two numbers is 15 and the sum of their squares is 113. Find the product of the numbers.

#966. A number when divided by 119 leaves a remainder of 19. What would the remainder be if the number is divided by 17?

#967. One-fourth of a herd of camels were seen in the forest. Twice the square root of the herd had gone to the mountains and the remaining 15 camels were seen on the bank of a river. Find the total number of camels.

#968. $6500 was divided among a certain number of persons. Had there been 15 persons more, each would have got $30 less. How many persons were originally there?

#969. The divisor is 25 times the quotient and 5 times the remainder. If the quotient is 16, what is the dividend?

#970. One-third of a tank holds 135 liters of water. What part of the tank is full when the tank contains 180 liters?

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#776 2008-12-11 01:43:51

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