Question

Emmanuel bought 40 lb of potting soil this week. This amount is 4 lb more than three times the amount of potting soil he bought last week. Answer the following questions to find the number of pounds of soil Emmanuel purchased last week.
(a) What is the unknown information?
(b) Let p represent the unknown information. Write an equation to model the problem. (c) Which number 10, 11, or 12 will solve the equation in Part B? Show your work. (d) How many pounds of potting soil did Emmanuel buy last week?

Answer 1

(a)
The unknown information is the amount of potting soil Emmanuel bought last week.

(b)
40 lb of potting soil is 4 lb more than 3 times p (the amount of potting soil he bought last week).

The equation:
$40=3p+4$

(c)
$40=3p+4 \ \ \ |\hbox{subtract 4} \\ 36=3p \ \ \ \ \ \ \ \ |\hbox{divide by 3} \\ p=12$

The solution to the equation is 12.

(d)
Last week Emmanuel bought 12 lb of potting soil.