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Finding the Fourth Proportional to 641.40, 885.20 and 375.88

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Solution

The fourth proportional to 641.40, 885.20 and 375.88 is: 518.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.40 : 885.20 = 375.88 : x
  2. Step 2: Convert to fraction form
    641.40/885.20 = 375.88/x
  3. Step 3: Cross multiply
    641.40x = 885.20 × 375.88
  4. Step 4: Simplify right side
    641.40x = 332,728.98
  5. Step 5: Solve for x
    x = 332,728.98/641.40
  6. Step 6: Final answer
    x = 518.75

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.