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Finding the Fourth Proportional to 688.29, 949.50 and 638.88

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Solution

The fourth proportional to 688.29, 949.50 and 638.88 is: 881.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.29 : 949.50 = 638.88 : x
  2. Step 2: Convert to fraction form
    688.29/949.50 = 638.88/x
  3. Step 3: Cross multiply
    688.29x = 949.50 × 638.88
  4. Step 4: Simplify right side
    688.29x = 606,616.56
  5. Step 5: Solve for x
    x = 606,616.56/688.29
  6. Step 6: Final answer
    x = 881.34

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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.