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Finding the Fourth Proportional to 639.30, 881.71 and 377.06

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Solution

The fourth proportional to 639.30, 881.71 and 377.06 is: 520.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.30 : 881.71 = 377.06 : x
  2. Step 2: Convert to fraction form
    639.30/881.71 = 377.06/x
  3. Step 3: Cross multiply
    639.30x = 881.71 × 377.06
  4. Step 4: Simplify right side
    639.30x = 332,458.83
  5. Step 5: Solve for x
    x = 332,458.83/639.30
  6. Step 6: Final answer
    x = 520.04

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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.