Finding the Fourth Proportional to 86.38, 129.49 and 40.70
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Solution
The fourth proportional to 86.38, 129.49 and 40.70 is: 61.02
Step by Step Solution
- Step 1: Write the proportion equation
86.38 : 129.49 = 40.70 : x - Step 2: Convert to fraction form
86.38/129.49 = 40.70/x - Step 3: Cross multiply
86.38x = 129.49 × 40.70 - Step 4: Simplify right side
86.38x = 5,270.46 - Step 5: Solve for x
x = 5,270.46/86.38 - Step 6: Final answer
x = 61.02
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.