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Finding the Fourth Proportional to 486.56, 671.39 and 279.56

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Solution

The fourth proportional to 486.56, 671.39 and 279.56 is: 385.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.56 : 671.39 = 279.56 : x
  2. Step 2: Convert to fraction form
    486.56/671.39 = 279.56/x
  3. Step 3: Cross multiply
    486.56x = 671.39 × 279.56
  4. Step 4: Simplify right side
    486.56x = 187,693.79
  5. Step 5: Solve for x
    x = 187,693.79/486.56
  6. Step 6: Final answer
    x = 385.76

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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.