Finding the Fourth Proportional to 81.19, 121.68 and 71.97
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Solution
The fourth proportional to 81.19, 121.68 and 71.97 is: 107.86
Step by Step Solution
- Step 1: Write the proportion equation
81.19 : 121.68 = 71.97 : x - Step 2: Convert to fraction form
81.19/121.68 = 71.97/x - Step 3: Cross multiply
81.19x = 121.68 × 71.97 - Step 4: Simplify right side
81.19x = 8,757.31 - Step 5: Solve for x
x = 8,757.31/81.19 - Step 6: Final answer
x = 107.86
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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.