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Finding the Fourth Proportional to 489.78, 675.83 and 279.97

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Solution

The fourth proportional to 489.78, 675.83 and 279.97 is: 386.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.78 : 675.83 = 279.97 : x
  2. Step 2: Convert to fraction form
    489.78/675.83 = 279.97/x
  3. Step 3: Cross multiply
    489.78x = 675.83 × 279.97
  4. Step 4: Simplify right side
    489.78x = 189,211.14
  5. Step 5: Solve for x
    x = 189,211.14/489.78
  6. Step 6: Final answer
    x = 386.32

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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.