Two numbers are 20% and 65% lesser than the third number. By what percent should the second number be increased so that it becomes equal to the first number?

128.5%

Let 3rd no. is = 100

ATQ,

          1st    :     2nd      :      3rd

           80   :       35       :      100

             ⇓            ⇓

              ↔ +45 ↔

45 is to be added in 2nd no. so that it becomes equal to 1nd.

Increased percentage = \(\frac{45}{35}\) × 100 = 128.5%