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Finding the Fourth Proportional to 279.40, 419.20 and 269.40

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Solution

The fourth proportional to 279.40, 419.20 and 269.40 is: 404.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.40 : 419.20 = 269.40 : x
  2. Step 2: Convert to fraction form
    279.40/419.20 = 269.40/x
  3. Step 3: Cross multiply
    279.40x = 419.20 × 269.40
  4. Step 4: Simplify right side
    279.40x = 112,932.48
  5. Step 5: Solve for x
    x = 112,932.48/279.40
  6. Step 6: Final answer
    x = 404.20

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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.