Finding the Fourth Proportional to 138.11, 207.17 and 77.19
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Solution
The fourth proportional to 138.11, 207.17 and 77.19 is: 115.79
Step by Step Solution
- Step 1: Write the proportion equation
138.11 : 207.17 = 77.19 : x - Step 2: Convert to fraction form
138.11/207.17 = 77.19/x - Step 3: Cross multiply
138.11x = 207.17 × 77.19 - Step 4: Simplify right side
138.11x = 15,991.97 - Step 5: Solve for x
x = 15,991.97/138.11 - Step 6: Final answer
x = 115.79
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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.