Finding the Fourth Proportional to 138.71, 208.17 and 80.99
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Solution
The fourth proportional to 138.71, 208.17 and 80.99 is: 121.55
Step by Step Solution
- Step 1: Write the proportion equation
138.71 : 208.17 = 80.99 : x - Step 2: Convert to fraction form
138.71/208.17 = 80.99/x - Step 3: Cross multiply
138.71x = 208.17 × 80.99 - Step 4: Simplify right side
138.71x = 16,859.69 - Step 5: Solve for x
x = 16,859.69/138.71 - Step 6: Final answer
x = 121.55
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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.