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Finding the Fourth Proportional to 521.53, 778.21 and 509.18

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Solution

The fourth proportional to 521.53, 778.21 and 509.18 is: 759.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.53 : 778.21 = 509.18 : x
  2. Step 2: Convert to fraction form
    521.53/778.21 = 509.18/x
  3. Step 3: Cross multiply
    521.53x = 778.21 × 509.18
  4. Step 4: Simplify right side
    521.53x = 396,242.53
  5. Step 5: Solve for x
    x = 396,242.53/521.53
  6. Step 6: Final answer
    x = 759.78

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.