Answer: There were 8 granola bars in each box, x = 8.
Step-by-step explanation:
The first step is write an equation:
4x + 5x = 72
The second step is to combine like terms:
4x + 5x = 72
9x = 72
Step 3 is to use the properties of equality and inverse operations to solve the equation:
9x/9 = 72/9
x = 8
Since x = 8, there were 8 granola bars in each box.
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