Finding the Fourth Proportional to 390.13, 585.07 and 207.42
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Solution
The fourth proportional to 390.13, 585.07 and 207.42 is: 311.07
Step by Step Solution
- Step 1: Write the proportion equation
390.13 : 585.07 = 207.42 : x - Step 2: Convert to fraction form
390.13/585.07 = 207.42/x - Step 3: Cross multiply
390.13x = 585.07 × 207.42 - Step 4: Simplify right side
390.13x = 121,357.20 - Step 5: Solve for x
x = 121,357.20/390.13 - Step 6: Final answer
x = 311.07
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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.