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Finding the Fourth Proportional to 639.87, 882.71 and 377.76

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Solution

The fourth proportional to 639.87, 882.71 and 377.76 is: 521.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.87 : 882.71 = 377.76 : x
  2. Step 2: Convert to fraction form
    639.87/882.71 = 377.76/x
  3. Step 3: Cross multiply
    639.87x = 882.71 × 377.76
  4. Step 4: Simplify right side
    639.87x = 333,450.64
  5. Step 5: Solve for x
    x = 333,450.64/639.87
  6. Step 6: Final answer
    x = 521.12

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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.