Finding the Fourth Proportional to 138.43, 207.66 and 47.19
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Solution
The fourth proportional to 138.43, 207.66 and 47.19 is: 70.79
Step by Step Solution
- Step 1: Write the proportion equation
138.43 : 207.66 = 47.19 : x - Step 2: Convert to fraction form
138.43/207.66 = 47.19/x - Step 3: Cross multiply
138.43x = 207.66 × 47.19 - Step 4: Simplify right side
138.43x = 9,799.24 - Step 5: Solve for x
x = 9,799.24/138.43 - Step 6: Final answer
x = 70.79
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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.