Finding the Fourth Proportional to 87.15, 130.74 and 39.09
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Solution
The fourth proportional to 87.15, 130.74 and 39.09 is: 58.64
Step by Step Solution
- Step 1: Write the proportion equation
87.15 : 130.74 = 39.09 : x - Step 2: Convert to fraction form
87.15/130.74 = 39.09/x - Step 3: Cross multiply
87.15x = 130.74 × 39.09 - Step 4: Simplify right side
87.15x = 5,110.63 - Step 5: Solve for x
x = 5,110.63/87.15 - Step 6: Final answer
x = 58.64
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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.