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Finding the Fourth Proportional to 489.18, 675.12 and 279.42

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Solution

The fourth proportional to 489.18, 675.12 and 279.42 is: 385.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.18 : 675.12 = 279.42 : x
  2. Step 2: Convert to fraction form
    489.18/675.12 = 279.42/x
  3. Step 3: Cross multiply
    489.18x = 675.12 × 279.42
  4. Step 4: Simplify right side
    489.18x = 188,642.03
  5. Step 5: Solve for x
    x = 188,642.03/489.18
  6. Step 6: Final answer
    x = 385.63

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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.