Solve Equations using the Division and Multiplication Properties of Equality: example 2.25

Denae bought 6 pounds of grapes for $10.74. What was the cost of one pound of grapes?

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Translate and solve:

Arianna bought a 24-pack of water bottles for $9.36. What was the cost of one water bottle?

How did it go?

What are you asked to find?	The cost of 1 pound of grapes
Assign a variable.	Let $c$ = the cost of one pound.
Write a sentence that gives the information to find it.	The cost of 6 pounds is $10.74.
Translate into an equation.	$6 c = 10.74$
Solve.	$\begin{matrix} \frac{6 c}{6} = \frac{10.74}{6} \\ c = 1.79 \end{matrix}$
	The grapes cost $1.79 per pound.
Check: If one pound costs $1.79, do 6 pounds cost #10.74? $\begin{matrix} 6 (1.79) & \overset{?}{=} & 10.74 \\ 10.74 & = & 10.74 ✓ \end{matrix}$

What are you asked to find?	The cost of 1 pound of grapes
Assign a variable.	Let $c$ = the cost of one pound.
Write a sentence that gives the information to find it.	The cost of 6 pounds is $10.74.
Translate into an equation.	$6 c = 10.74$
Solve.	$\begin{matrix} \frac{6 c}{6} = \frac{10.74}{6} \\ c = 1.79 \end{matrix}$
	The grapes cost $1.79 per pound.
Check: If one pound costs $1.79, do 6 pounds cost #10.74? $\begin{matrix} 6 (1.79) & \overset{?}{=} & 10.74 \\ 10.74 & = & 10.74 ✓ \end{matrix}$