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Finding the Fourth Proportional to 486.76, 671.71 and 279.76

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Solution

The fourth proportional to 486.76, 671.71 and 279.76 is: 386.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.76 : 671.71 = 279.76 : x
  2. Step 2: Convert to fraction form
    486.76/671.71 = 279.76/x
  3. Step 3: Cross multiply
    486.76x = 671.71 × 279.76
  4. Step 4: Simplify right side
    486.76x = 187,917.59
  5. Step 5: Solve for x
    x = 187,917.59/486.76
  6. Step 6: Final answer
    x = 386.06

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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.