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Finding the Fourth Proportional to 667.28, 999.88 and 520.68

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Solution

The fourth proportional to 667.28, 999.88 and 520.68 is: 780.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    667.28 : 999.88 = 520.68 : x
  2. Step 2: Convert to fraction form
    667.28/999.88 = 520.68/x
  3. Step 3: Cross multiply
    667.28x = 999.88 × 520.68
  4. Step 4: Simplify right side
    667.28x = 520,616.54
  5. Step 5: Solve for x
    x = 520,616.54/667.28
  6. Step 6: Final answer
    x = 780.21

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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.