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Finding the Fourth Proportional to 641.20, 961.80 and 446.80

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Solution

The fourth proportional to 641.20, 961.80 and 446.80 is: 670.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.20 : 961.80 = 446.80 : x
  2. Step 2: Convert to fraction form
    641.20/961.80 = 446.80/x
  3. Step 3: Cross multiply
    641.20x = 961.80 × 446.80
  4. Step 4: Simplify right side
    641.20x = 429,732.24
  5. Step 5: Solve for x
    x = 429,732.24/641.20
  6. Step 6: Final answer
    x = 670.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.