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Finding the Fourth Proportional to 521.25, 781.38 and 213.03

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Solution

The fourth proportional to 521.25, 781.38 and 213.03 is: 319.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.25 : 781.38 = 213.03 : x
  2. Step 2: Convert to fraction form
    521.25/781.38 = 213.03/x
  3. Step 3: Cross multiply
    521.25x = 781.38 × 213.03
  4. Step 4: Simplify right side
    521.25x = 166,457.38
  5. Step 5: Solve for x
    x = 166,457.38/521.25
  6. Step 6: Final answer
    x = 319.34

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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.