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Finding the Fourth Proportional to 288.60, 398.82 and 279.12

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Solution

The fourth proportional to 288.60, 398.82 and 279.12 is: 385.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.60 : 398.82 = 279.12 : x
  2. Step 2: Convert to fraction form
    288.60/398.82 = 279.12/x
  3. Step 3: Cross multiply
    288.60x = 398.82 × 279.12
  4. Step 4: Simplify right side
    288.60x = 111,318.64
  5. Step 5: Solve for x
    x = 111,318.64/288.60
  6. Step 6: Final answer
    x = 385.72

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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.