Two numbers are respectively twenty percent and ten percent more than the third number. How many percent is the first number more than the second?

10%

Step-by-step explanation:

Let the third number is X.

then first number = (100-30) % of X

= 70% of X = 7X/10

Second number is (63X/100)

Difference = 7X/10 - 63X/100 = 7X/10

So required percentage is, difference is what percent of first number

=> (7X/100 * 10/7X * 100) % = 10%