CAT Exam Numerical Ability Algebra

suresh kumar went to the market with 100 rs if he buys three pens and 6 pencils he uses up all his money but if he buys three pencils and 6 pens he falls short by 20% if he wants to buy equal no. of pens and pencils how many pencils can he buy?

Read Solution (Total 3)

3x+6y=100
6x+3y=125 (short by 20%, i.e (80/100)x=100)

add both
9(x+y)=225
x+y=25
total is 100 rs means 25 has to multiply with 4
therefore, 4x + 4y=100 (equal number of pen+ pencil hogya)
So, Answer is 4
7 years agoHelpfull: Yes(2) No(4)

3
3a+6b=100
3b+6a=120

after substration 3a+3b=80
ans 80
8 years agoHelpfull: Yes(1) No(8)
4
1 pencil costs 20
1 pen cost 26.66
6 years agoHelpfull: Yes(0) No(0)

CAT Other Question

In how many ways 34300 can written as product of 8 different integers? Imagine a conveyor belt, with tins placed at regular intervals onto the belt at one end, moving along at a steady rate towards a labeling machine at the far end. A rabbit starts from a tin at the beginning of the belt and steadily jumps from tin to tin, finally jumping off immediately before the labeling machine.
When the rabbit jumps at a rate of one jump per second he arrives at the labeling machine in 20 jumps but if he speeds up and manages two jumps per second he can fit in 32 jumps before the end of the line.

How many tins are there on the line ?