Finding the Fourth Proportional to 86.36, 129.40 and 49.70
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Solution
The fourth proportional to 86.36, 129.40 and 49.70 is: 74.47
Step by Step Solution
- Step 1: Write the proportion equation
86.36 : 129.40 = 49.70 : x - Step 2: Convert to fraction form
86.36/129.40 = 49.70/x - Step 3: Cross multiply
86.36x = 129.40 × 49.70 - Step 4: Simplify right side
86.36x = 6,431.18 - Step 5: Solve for x
x = 6,431.18/86.36 - Step 6: Final answer
x = 74.47
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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.