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Finding the Fourth Proportional to 639.76, 951.99 and 637.60

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Solution

The fourth proportional to 639.76, 951.99 and 637.60 is: 948.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.76 : 951.99 = 637.60 : x
  2. Step 2: Convert to fraction form
    639.76/951.99 = 637.60/x
  3. Step 3: Cross multiply
    639.76x = 951.99 × 637.60
  4. Step 4: Simplify right side
    639.76x = 606,988.82
  5. Step 5: Solve for x
    x = 606,988.82/639.76
  6. Step 6: Final answer
    x = 948.78

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.