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Finding the Fourth Proportional to 639.84, 877.11 and 630.12

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Solution

The fourth proportional to 639.84, 877.11 and 630.12 is: 863.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.84 : 877.11 = 630.12 : x
  2. Step 2: Convert to fraction form
    639.84/877.11 = 630.12/x
  3. Step 3: Cross multiply
    639.84x = 877.11 × 630.12
  4. Step 4: Simplify right side
    639.84x = 552,684.55
  5. Step 5: Solve for x
    x = 552,684.55/639.84
  6. Step 6: Final answer
    x = 863.79

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.