Hi Kewan,
We solve this problem through the following steps:
Step One: Since we know the total number of mufflers is 22, we can create the let statements:
Let x = the number of premium mufflers
Let 22-x=the number of normal mufflers
Step Two: We then create an equation to relate the number of mufflers to the price and solve for x:
23(x)+16(22-x)=422 Distribute
7x+352=422 Combine Like Terms
7x=422-352 Subtract 352 from both sides of the equation
7x=70
x=10
∴We have 10 premium mufflers in stock.
Best,
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