Finding the Fourth Proportional to 87.20, 130.70 and 66.99
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Solution
The fourth proportional to 87.20, 130.70 and 66.99 is: 100.41
Step by Step Solution
- Step 1: Write the proportion equation
87.20 : 130.70 = 66.99 : x - Step 2: Convert to fraction form
87.20/130.70 = 66.99/x - Step 3: Cross multiply
87.20x = 130.70 × 66.99 - Step 4: Simplify right side
87.20x = 8,755.26 - Step 5: Solve for x
x = 8,755.26/87.20 - Step 6: Final answer
x = 100.41
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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.