PETE C. answered 01/28/20
SAT MATH
Let B = number of SMALLER boxes
Let 2B = number of LARGER boxes, since twice as many large boxes shipped than smaller boxes
7B + (2)(13)B = 165 (SMALLER box=7 cu ft and LARGER box=13 cu ft.)
7B + 26B = 165
33B = 165
B = 5 (Dividing both sides by 33.)
Therefore, 5 SMALL boxes were shipped and 10 LARGE boxes were shipped(2x5).
CHECKING:
5 small boxes X 7 cu ft = 35 cu ft
10 large boxes X 13 cu ft = 130 cu ft
130 cu ft + 35 cu ft = 165 cu ft