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Finding the Fourth Proportional to 639.40, 881.96 and 532.78

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Solution

The fourth proportional to 639.40, 881.96 and 532.78 is: 734.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.40 : 881.96 = 532.78 : x
  2. Step 2: Convert to fraction form
    639.40/881.96 = 532.78/x
  3. Step 3: Cross multiply
    639.40x = 881.96 × 532.78
  4. Step 4: Simplify right side
    639.40x = 469,890.65
  5. Step 5: Solve for x
    x = 469,890.65/639.40
  6. Step 6: Final answer
    x = 734.89

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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.