out of 9 persons , 8 persons spent rs . 30 each for their meals . the ninth one spent rs . 20 more than the average expenditure of all the 9 . the total money spent by all of them was
explanation : let the average expenditure be rs . x then , 9 x = [ 8 × 30 + ( x + 20 ) ] ⇔ 9 x = x + 260 ⇔ x = 32.50 total money spent = 9 x = rs . ( 9 x 32.5 o ) = rs 292 . 50 answer : a
add(multiply(8, 30), divide(add(multiply(8, 30), multiply(9, 20)), 8))