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Finding the Fourth Proportional to 521.32, 781.36 and 290.09

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Solution

The fourth proportional to 521.32, 781.36 and 290.09 is: 434.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.32 : 781.36 = 290.09 : x
  2. Step 2: Convert to fraction form
    521.32/781.36 = 290.09/x
  3. Step 3: Cross multiply
    521.32x = 781.36 × 290.09
  4. Step 4: Simplify right side
    521.32x = 226,664.72
  5. Step 5: Solve for x
    x = 226,664.72/521.32
  6. Step 6: Final answer
    x = 434.79

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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.