Question

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

Answer 1

Pretty sure the correct answer is B.

(8+2)+(9+1)

Answer 2

I would suppose B would be the simplest? because 8 and 2 result to 10 and 9 and 1 result to ten, so then you would just have to add 10 and 10.