Finding the Fourth Proportional to 138.24, 207.39 and 115.19
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Solution
The fourth proportional to 138.24, 207.39 and 115.19 is: 172.80
Step by Step Solution
- Step 1: Write the proportion equation
138.24 : 207.39 = 115.19 : x - Step 2: Convert to fraction form
138.24/207.39 = 115.19/x - Step 3: Cross multiply
138.24x = 207.39 × 115.19 - Step 4: Simplify right side
138.24x = 23,888.22 - Step 5: Solve for x
x = 23,888.22/138.24 - Step 6: Final answer
x = 172.80
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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.