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Finding the Fourth Proportional to 641.79, 879.89 and 630.11

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Solution

The fourth proportional to 641.79, 879.89 and 630.11 is: 863.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.79 : 879.89 = 630.11 : x
  2. Step 2: Convert to fraction form
    641.79/879.89 = 630.11/x
  3. Step 3: Cross multiply
    641.79x = 879.89 × 630.11
  4. Step 4: Simplify right side
    641.79x = 554,430.08
  5. Step 5: Solve for x
    x = 554,430.08/641.79
  6. Step 6: Final answer
    x = 863.88

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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.