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Finding the Fourth Proportional to 489.10, 674.79 and 279.28

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Solution

The fourth proportional to 489.10, 674.79 and 279.28 is: 385.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.10 : 674.79 = 279.28 : x
  2. Step 2: Convert to fraction form
    489.10/674.79 = 279.28/x
  3. Step 3: Cross multiply
    489.10x = 674.79 × 279.28
  4. Step 4: Simplify right side
    489.10x = 188,455.35
  5. Step 5: Solve for x
    x = 188,455.35/489.10
  6. Step 6: Final answer
    x = 385.31

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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.