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Finding the Fourth Proportional to 639.80, 882.96 and 377.86

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Solution

The fourth proportional to 639.80, 882.96 and 377.86 is: 521.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.80 : 882.96 = 377.86 : x
  2. Step 2: Convert to fraction form
    639.80/882.96 = 377.86/x
  3. Step 3: Cross multiply
    639.80x = 882.96 × 377.86
  4. Step 4: Simplify right side
    639.80x = 333,635.27
  5. Step 5: Solve for x
    x = 333,635.27/639.80
  6. Step 6: Final answer
    x = 521.47

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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.