Finding the Fourth Proportional to 138.14, 207.20 and 69.65
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Solution
The fourth proportional to 138.14, 207.20 and 69.65 is: 104.47
Step by Step Solution
- Step 1: Write the proportion equation
138.14 : 207.20 = 69.65 : x - Step 2: Convert to fraction form
138.14/207.20 = 69.65/x - Step 3: Cross multiply
138.14x = 207.20 × 69.65 - Step 4: Simplify right side
138.14x = 14,430.62 - Step 5: Solve for x
x = 14,430.62/138.14 - Step 6: Final answer
x = 104.47
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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.