Finding the Fourth Proportional to 138.20, 207.18 and 56.99
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Solution
The fourth proportional to 138.20, 207.18 and 56.99 is: 85.43
Step by Step Solution
- Step 1: Write the proportion equation
138.20 : 207.18 = 56.99 : x - Step 2: Convert to fraction form
138.20/207.18 = 56.99/x - Step 3: Cross multiply
138.20x = 207.18 × 56.99 - Step 4: Simplify right side
138.20x = 11,805.87 - Step 5: Solve for x
x = 11,805.87/138.20 - Step 6: Final answer
x = 85.43
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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.