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Finding the Fourth Proportional to 279.86, 385.75 and 220.75

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Solution

The fourth proportional to 279.86, 385.75 and 220.75 is: 304.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.86 : 385.75 = 220.75 : x
  2. Step 2: Convert to fraction form
    279.86/385.75 = 220.75/x
  3. Step 3: Cross multiply
    279.86x = 385.75 × 220.75
  4. Step 4: Simplify right side
    279.86x = 85,153.62
  5. Step 5: Solve for x
    x = 85,153.62/279.86
  6. Step 6: Final answer
    x = 304.28

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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.