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Finding the Fourth Proportional to 520.80, 781.20 and 358.32

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Solution

The fourth proportional to 520.80, 781.20 and 358.32 is: 537.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.80 : 781.20 = 358.32 : x
  2. Step 2: Convert to fraction form
    520.80/781.20 = 358.32/x
  3. Step 3: Cross multiply
    520.80x = 781.20 × 358.32
  4. Step 4: Simplify right side
    520.80x = 279,919.58
  5. Step 5: Solve for x
    x = 279,919.58/520.80
  6. Step 6: Final answer
    x = 537.48

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Double scale
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Similar ratio
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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.