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Finding the Fourth Proportional to 638.71, 881.41 and 373.21

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Solution

The fourth proportional to 638.71, 881.41 and 373.21 is: 515.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.71 : 881.41 = 373.21 : x
  2. Step 2: Convert to fraction form
    638.71/881.41 = 373.21/x
  3. Step 3: Cross multiply
    638.71x = 881.41 × 373.21
  4. Step 4: Simplify right side
    638.71x = 328,951.03
  5. Step 5: Solve for x
    x = 328,951.03/638.71
  6. Step 6: Final answer
    x = 515.02

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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.