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Finding the Fourth Proportional to 521.08, 781.21 and 260.95

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Solution

The fourth proportional to 521.08, 781.21 and 260.95 is: 391.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.08 : 781.21 = 260.95 : x
  2. Step 2: Convert to fraction form
    521.08/781.21 = 260.95/x
  3. Step 3: Cross multiply
    521.08x = 781.21 × 260.95
  4. Step 4: Simplify right side
    521.08x = 203,856.75
  5. Step 5: Solve for x
    x = 203,856.75/521.08
  6. Step 6: Final answer
    x = 391.22

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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.