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Finding the Fourth Proportional to 500.28, 690.39 and 279.20

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Solution

The fourth proportional to 500.28, 690.39 and 279.20 is: 385.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.28 : 690.39 = 279.20 : x
  2. Step 2: Convert to fraction form
    500.28/690.39 = 279.20/x
  3. Step 3: Cross multiply
    500.28x = 690.39 × 279.20
  4. Step 4: Simplify right side
    500.28x = 192,753.44
  5. Step 5: Solve for x
    x = 192,753.44/500.28
  6. Step 6: Final answer
    x = 385.29

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.