Finding the Third Proportional to 78 and 87.75
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Solution
The third proportional to 78 and 87.75 is: 98.72
Step by Step Solution
- Step 1: Write the proportion equation
78 : 87.75 = 87.75 : x - Step 2: Convert to fraction form
78/87.75 = 87.75/x - Step 3: Cross multiply
78x = 87.75 × 87.75 - Step 4: Simplify right side
78x = 7,700.06 - Step 5: Solve for x
x = 7,700.06/78 - Step 6: Final answer
x = 98.72
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These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.