Question

The number whose square is equal to the difference of the squares of 75.15 and 60.12 is 

(a) 46.09 

(b) 48.09 

(c) 45.09 

(d) 47.09

Answer 1

(c) 45.09

Let the required number be x. Then. 

x² = (75.15)² – (60.12)²

= (75.15 + 60.12) (75.15 – 60.12) 

= 135.27 × 15.03 = 2033.1081

\(\therefore\) x = \(\sqrt{2033.1081}\)

= 45.09