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Finding the Fourth Proportional to 489.38, 675.41 and 315.09

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Solution

The fourth proportional to 489.38, 675.41 and 315.09 is: 434.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.38 : 675.41 = 315.09 : x
  2. Step 2: Convert to fraction form
    489.38/675.41 = 315.09/x
  3. Step 3: Cross multiply
    489.38x = 675.41 × 315.09
  4. Step 4: Simplify right side
    489.38x = 212,813.36
  5. Step 5: Solve for x
    x = 212,813.36/489.38
  6. Step 6: Final answer
    x = 434.87

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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.