Numbers Aptitude Test Paper 7

Answer: D

Explanation:
Largest 4-digit number = 9999

So, the number is: 9999 - 33 = 9966.

Answer: C

Explanation:
Solve (1+1/x) = (x+1)/x, then
1+1/ ((x+1)/x) = (2x+1)/ (x+1), then
1+1/ ((2x+1)/(x+1)) = (3x+2)/ (2x+1), then
1+1/ ((3x+2)/ (2x+1)) = (5x+3)/ (3x+2)
Hence, we get (5x+3)/ (3x+2)

Answer: A

Explanation:
A number, which is divisible by 3, 5, and 9, is also divisible by 45.

A number is divisible by 3 if the sum of its entire digits is divisible by 3.
A number is divisible by 9 if the sum of its entire digits is divisible by 9.
The number which ends with 0 or 5 is divisible by 5.

The number 306990 fulfils all the requirements, so the answer is 306990.