( 51 + 52 + 53 + . . . + 100 ) = ?
"explanation : this is an a . p . in which a = 51 , l = 100 and n = 50 . sum = n ( a + l ) = 50 x ( 51 + 100 ) = ( 25 x 151 ) = 3775 . 2 2 answer : d"
divide(add(51, 52), 53)