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Finding the Fourth Proportional to 279.38, 386.12 and 217.15

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Solution

The fourth proportional to 279.38, 386.12 and 217.15 is: 300.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.38 : 386.12 = 217.15 : x
  2. Step 2: Convert to fraction form
    279.38/386.12 = 217.15/x
  3. Step 3: Cross multiply
    279.38x = 386.12 × 217.15
  4. Step 4: Simplify right side
    279.38x = 83,845.75
  5. Step 5: Solve for x
    x = 83,845.75/279.38
  6. Step 6: Final answer
    x = 300.11

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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.