Answer:
Expression is :
![0.60(90-x)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/1wv3o67n21dl8l5upwivf1aio4ueol42gv.png)
Explanation:
A grocer bought some walnuts for 45¢ per pound.
He also bought pecans for 60¢ per pound.
He wants to mix the pecans and walnuts together to form a 90 pound mixture to sell at 55 cents per pound.
Let x represents the pounds of walnuts used in the mixture, so 90-x will represent the pounds of pecans.
Hence, the expression that will represent the total cost of the pecans used in the mixture will be :
![0.60(90-x)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/1wv3o67n21dl8l5upwivf1aio4ueol42gv.png)