Finding the Fourth Proportional to 129.13, 193.73 and 81
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Solution
The fourth proportional to 129.13, 193.73 and 81 is: 121.52
Step by Step Solution
- Step 1: Write the proportion equation
129.13 : 193.73 = 81 : x - Step 2: Convert to fraction form
129.13/193.73 = 81/x - Step 3: Cross multiply
129.13x = 193.73 × 81 - Step 4: Simplify right side
129.13x = 15,691.73 - Step 5: Solve for x
x = 15,691.73/129.13 - Step 6: Final answer
x = 121.52
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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.