Finding the Fourth Proportional to 138.87, 208.08 and 84.61
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Solution
The fourth proportional to 138.87, 208.08 and 84.61 is: 126.77
Step by Step Solution
- Step 1: Write the proportion equation
138.87 : 208.08 = 84.61 : x - Step 2: Convert to fraction form
138.87/208.08 = 84.61/x - Step 3: Cross multiply
138.87x = 208.08 × 84.61 - Step 4: Simplify right side
138.87x = 17,605.23 - Step 5: Solve for x
x = 17,605.23/138.87 - Step 6: Final answer
x = 126.77
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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.