During a marathon race an athlete loses 2 % of his mass. At the end of the race his mass is 67.13 kg.
Calculate his mass before the race.

his mass before the race was 68.5kg

Step-by-step explanation:

let,his mass before the race was 'x'

By question,

x-2% of x =67.13

or,x- 2x/100=67.13

or, 98x/100=67.13

or,98x=67.13×100

or,98x=6713

or,x=6713÷98

or,x=68.5

thus,his mass before the race was 68.5 kg

+25 = x

step-by-step explanation:

here x is the hypotenuse of a right triangle whose legs are 7 and 24.   by the pythagorean theorem, 7² + 24² must equal x²:

x² = 49 + 576 = 625.   thus, x = +√625 = +25 = x

step-by-step explanation: