Describe a real - word situation that could be represented by the expression 18 - 3t. what does t represent.

For an example whats this 3 + L = 12   

so what can you add to three to get twelve get it thought so

that would be 9

for this question or equation you might say

All you have to do is ask your self What can the t be  

try it and tell me what you get

The word EACH in math means multiply!

Therefore 11 X 8 = 88 cubic feet form the small boxes.
23 X 13 = 299 cubic feet for the large boxes
TOTAL = SMALL + LARGE
TOTAL = 88 + 299 = 387 cubic feet

Part 2: total = small + large
Each small is 8 cubic feet and the number of small boxes is “s” so each means multiply so 8s gives us the total volume from small boxes. Large boxes are 23 each so:
Total = 8s + 23l