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Finding the Fourth Proportional to 521.28, 782.12 and 315.99

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Solution

The fourth proportional to 521.28, 782.12 and 315.99 is: 474.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.28 : 782.12 = 315.99 : x
  2. Step 2: Convert to fraction form
    521.28/782.12 = 315.99/x
  3. Step 3: Cross multiply
    521.28x = 782.12 × 315.99
  4. Step 4: Simplify right side
    521.28x = 247,140.52
  5. Step 5: Solve for x
    x = 247,140.52/521.28
  6. Step 6: Final answer
    x = 474.10

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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.