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Finding the Fourth Proportional to 489.72, 675.69 and 279.86

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Solution

The fourth proportional to 489.72, 675.69 and 279.86 is: 386.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.72 : 675.69 = 279.86 : x
  2. Step 2: Convert to fraction form
    489.72/675.69 = 279.86/x
  3. Step 3: Cross multiply
    489.72x = 675.69 × 279.86
  4. Step 4: Simplify right side
    489.72x = 189,100.44
  5. Step 5: Solve for x
    x = 189,100.44/489.72
  6. Step 6: Final answer
    x = 386.14

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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.