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Finding the Fourth Proportional to 669.16, 1,002.12 and 380.80

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Solution

The fourth proportional to 669.16, 1,002.12 and 380.80 is: 570.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.16 : 1,002.12 = 380.80 : x
  2. Step 2: Convert to fraction form
    669.16/1,002.12 = 380.80/x
  3. Step 3: Cross multiply
    669.16x = 1,002.12 × 380.80
  4. Step 4: Simplify right side
    669.16x = 381,607.30
  5. Step 5: Solve for x
    x = 381,607.30/669.16
  6. Step 6: Final answer
    x = 570.28

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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.