Basic Simplification Quiz Set 020

This is a multiplication by a power of 5. The best way is to observe that 125 = 5³. There are 3 powers of 5. So append 3 zeroes and divide by 2³, like this: $320000/8$ = 40000.

Let the score in English be E, then his score in math is 432 - E. We have also been given $(432 - E)/12 = E/21 + 25$. Solving for E, we get E = 84.

Let the number of blue marbles at present be x. The number of pink marbles at present are 5x. If we put back 27 blue marbles, the equation becomes x + 27 = 2 × 5x, which gives 9x = 27, or x = 3 marbles. Note: some information in the question is never used, it is given for confusing the candidate.

If x is the amount, $x/17 - x/23 = 48$, which can be re-arranged to get x = ${48 × 23 × 17}/{23 - 17}$ = Rs. 3128.

We have to find $25{3/10}$ - $10{3/25}$, which is same as ${253/10}$ - ${253/25}$ = 253 × ${25 - 10}/{25 × 10}$ = ${759/50}$. So ${759/50}$, which is same as: $15{9/50}$ is the required answer.