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Finding the Fourth Proportional to 489.45, 675.41 and 279.64

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Solution

The fourth proportional to 489.45, 675.41 and 279.64 is: 385.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.45 : 675.41 = 279.64 : x
  2. Step 2: Convert to fraction form
    489.45/675.41 = 279.64/x
  3. Step 3: Cross multiply
    489.45x = 675.41 × 279.64
  4. Step 4: Simplify right side
    489.45x = 188,871.65
  5. Step 5: Solve for x
    x = 188,871.65/489.45
  6. Step 6: Final answer
    x = 385.89

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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.