Finding the Fourth Proportional to 86.19, 129.12 and 74.62
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Solution
The fourth proportional to 86.19, 129.12 and 74.62 is: 111.79
Step by Step Solution
- Step 1: Write the proportion equation
86.19 : 129.12 = 74.62 : x - Step 2: Convert to fraction form
86.19/129.12 = 74.62/x - Step 3: Cross multiply
86.19x = 129.12 × 74.62 - Step 4: Simplify right side
86.19x = 9,634.93 - Step 5: Solve for x
x = 9,634.93/86.19 - Step 6: Final answer
x = 111.79
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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.