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Finding the Fourth Proportional to 520.28, 780.62 and 315

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Solution

The fourth proportional to 520.28, 780.62 and 315 is: 472.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.28 : 780.62 = 315 : x
  2. Step 2: Convert to fraction form
    520.28/780.62 = 315/x
  3. Step 3: Cross multiply
    520.28x = 780.62 × 315
  4. Step 4: Simplify right side
    520.28x = 245,895.30
  5. Step 5: Solve for x
    x = 245,895.30/520.28
  6. Step 6: Final answer
    x = 472.62

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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.