Finding the Fourth Proportional to 139.75, 209.61 and 82
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Solution
The fourth proportional to 139.75, 209.61 and 82 is: 122.99
Step by Step Solution
- Step 1: Write the proportion equation
139.75 : 209.61 = 82 : x - Step 2: Convert to fraction form
139.75/209.61 = 82/x - Step 3: Cross multiply
139.75x = 209.61 × 82 - Step 4: Simplify right side
139.75x = 17,188.02 - Step 5: Solve for x
x = 17,188.02/139.75 - Step 6: Final answer
x = 122.99
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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.