Directions (Set of 5 questions): What approximate value should come in place of the question marks(?) in the following questions? (Note : you are not expected to calculate the exact value.)
$\left( 358\times 17.72 \right)\div 6.21+1188.69=~?~+\sqrt{7.2\times 20+25}$
Solution
$\left( 358\times 17.72 \right)\div 6.21+1188.69=~?~+\sqrt{7.2\times 20+25}$
$?\approx \left( 358\times 18 \right)\div 6+1189-\sqrt{144+25}$
$?\approx 1074+1189-13$
$?=2263-13$
$? = 2250$