APPROXIMATIONS-1

Estimate the value of 87 x 71.

solution

round off to tens;

87 ≈ 90  [approximating to 90]

71 ≈ 70  [approximating to 70]

 = 90 x 70

 = 6300

Hence 87 x 71 ≈ 6300

TRY THIS...................

Estimate the value of 61 x 69.[ans. 4200]