Finding the Fourth Proportional to 139.60, 209.42 and 71.09
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Solution
The fourth proportional to 139.60, 209.42 and 71.09 is: 106.65
Step by Step Solution
- Step 1: Write the proportion equation
139.60 : 209.42 = 71.09 : x - Step 2: Convert to fraction form
139.60/209.42 = 71.09/x - Step 3: Cross multiply
139.60x = 209.42 × 71.09 - Step 4: Simplify right side
139.60x = 14,887.31 - Step 5: Solve for x
x = 14,887.31/139.60 - Step 6: Final answer
x = 106.65
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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.