Finding the Fourth Proportional to 139.53, 209.10 and 115.31
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Solution
The fourth proportional to 139.53, 209.10 and 115.31 is: 172.80
Step by Step Solution
- Step 1: Write the proportion equation
139.53 : 209.10 = 115.31 : x - Step 2: Convert to fraction form
139.53/209.10 = 115.31/x - Step 3: Cross multiply
139.53x = 209.10 × 115.31 - Step 4: Simplify right side
139.53x = 24,111.10 - Step 5: Solve for x
x = 24,111.10/139.53 - Step 6: Final answer
x = 172.80
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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.