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Finding the Fourth Proportional to 279.90, 385.97 and 220.79

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Solution

The fourth proportional to 279.90, 385.97 and 220.79 is: 304.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.90 : 385.97 = 220.79 : x
  2. Step 2: Convert to fraction form
    279.90/385.97 = 220.79/x
  3. Step 3: Cross multiply
    279.90x = 385.97 × 220.79
  4. Step 4: Simplify right side
    279.90x = 85,215.28
  5. Step 5: Solve for x
    x = 85,215.28/279.90
  6. Step 6: Final answer
    x = 304.45

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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.