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Finding the Fourth Proportional to 521.30, 781.25 and 243.47

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Solution

The fourth proportional to 521.30, 781.25 and 243.47 is: 364.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.30 : 781.25 = 243.47 : x
  2. Step 2: Convert to fraction form
    521.30/781.25 = 243.47/x
  3. Step 3: Cross multiply
    521.30x = 781.25 × 243.47
  4. Step 4: Simplify right side
    521.30x = 190,211.67
  5. Step 5: Solve for x
    x = 190,211.67/521.30
  6. Step 6: Final answer
    x = 364.88

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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.