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Finding the Fourth Proportional to 521.29, 781.71 and 213.06

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Solution

The fourth proportional to 521.29, 781.71 and 213.06 is: 319.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.29 : 781.71 = 213.06 : x
  2. Step 2: Convert to fraction form
    521.29/781.71 = 213.06/x
  3. Step 3: Cross multiply
    521.29x = 781.71 × 213.06
  4. Step 4: Simplify right side
    521.29x = 166,551.13
  5. Step 5: Solve for x
    x = 166,551.13/521.29
  6. Step 6: Final answer
    x = 319.50

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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.