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Finding the Fourth Proportional to 489.31, 675.27 and 279.49

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Solution

The fourth proportional to 489.31, 675.27 and 279.49 is: 385.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.31 : 675.27 = 279.49 : x
  2. Step 2: Convert to fraction form
    489.31/675.27 = 279.49/x
  3. Step 3: Cross multiply
    489.31x = 675.27 × 279.49
  4. Step 4: Simplify right side
    489.31x = 188,731.21
  5. Step 5: Solve for x
    x = 188,731.21/489.31
  6. Step 6: Final answer
    x = 385.71

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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.