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Finding the Fourth Proportional to 521.91, 781.65 and 290.43

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Solution

The fourth proportional to 521.91, 781.65 and 290.43 is: 434.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.91 : 781.65 = 290.43 : x
  2. Step 2: Convert to fraction form
    521.91/781.65 = 290.43/x
  3. Step 3: Cross multiply
    521.91x = 781.65 × 290.43
  4. Step 4: Simplify right side
    521.91x = 227,014.61
  5. Step 5: Solve for x
    x = 227,014.61/521.91
  6. Step 6: Final answer
    x = 434.97

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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.