Finding the Fourth Proportional to 138.13, 207.07 and 79.65
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Solution
The fourth proportional to 138.13, 207.07 and 79.65 is: 119.40
Step by Step Solution
- Step 1: Write the proportion equation
138.13 : 207.07 = 79.65 : x - Step 2: Convert to fraction form
138.13/207.07 = 79.65/x - Step 3: Cross multiply
138.13x = 207.07 × 79.65 - Step 4: Simplify right side
138.13x = 16,493.13 - Step 5: Solve for x
x = 16,493.13/138.13 - Step 6: Final answer
x = 119.40
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.