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Finding the Fourth Proportional to 641.20, 890.80 and 635.20

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Solution

The fourth proportional to 641.20, 890.80 and 635.20 is: 882.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.20 : 890.80 = 635.20 : x
  2. Step 2: Convert to fraction form
    641.20/890.80 = 635.20/x
  3. Step 3: Cross multiply
    641.20x = 890.80 × 635.20
  4. Step 4: Simplify right side
    641.20x = 565,836.16
  5. Step 5: Solve for x
    x = 565,836.16/641.20
  6. Step 6: Final answer
    x = 882.46

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.