Select the proper placement for parentheses to speed up the addition for the expression 2 + 9 + 8 + 1 A. (1 + 2) + (9 + 8) B. (8 + 9) + (2 + 1) C. (9 + 2) + (8 + 1) D. (8 + 2) + (9 + 1)

Respuesta :

the answer is D. Because it is easier to add 9 and 2 and also 8 and 1.
It's D because
(8+2) = 10
(9+1) = 10
Hope this helped. (: