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Finding the Fourth Proportional to 308.70, 462.20 and 279.90

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Solution

The fourth proportional to 308.70, 462.20 and 279.90 is: 419.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.70 : 462.20 = 279.90 : x
  2. Step 2: Convert to fraction form
    308.70/462.20 = 279.90/x
  3. Step 3: Cross multiply
    308.70x = 462.20 × 279.90
  4. Step 4: Simplify right side
    308.70x = 129,368.38
  5. Step 5: Solve for x
    x = 129,368.38/308.70
  6. Step 6: Final answer
    x = 419.07

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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.