Finding the Fourth Proportional to 81.57, 122.43 and 38.31
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Solution
The fourth proportional to 81.57, 122.43 and 38.31 is: 57.50
Step by Step Solution
- Step 1: Write the proportion equation
81.57 : 122.43 = 38.31 : x - Step 2: Convert to fraction form
81.57/122.43 = 38.31/x - Step 3: Cross multiply
81.57x = 122.43 × 38.31 - Step 4: Simplify right side
81.57x = 4,690.29 - Step 5: Solve for x
x = 4,690.29/81.57 - Step 6: Final answer
x = 57.50
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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.