Finding the Fourth Proportional to 81.20, 121.68 and 58.08
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Solution
The fourth proportional to 81.20, 121.68 and 58.08 is: 87.03
Step by Step Solution
- Step 1: Write the proportion equation
81.20 : 121.68 = 58.08 : x - Step 2: Convert to fraction form
81.20/121.68 = 58.08/x - Step 3: Cross multiply
81.20x = 121.68 × 58.08 - Step 4: Simplify right side
81.20x = 7,067.17 - Step 5: Solve for x
x = 7,067.17/81.20 - Step 6: Final answer
x = 87.03
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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.