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Finding the Fourth Proportional to 638.47, 879.96 and 520.19

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Solution

The fourth proportional to 638.47, 879.96 and 520.19 is: 716.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.47 : 879.96 = 520.19 : x
  2. Step 2: Convert to fraction form
    638.47/879.96 = 520.19/x
  3. Step 3: Cross multiply
    638.47x = 879.96 × 520.19
  4. Step 4: Simplify right side
    638.47x = 457,746.39
  5. Step 5: Solve for x
    x = 457,746.39/638.47
  6. Step 6: Final answer
    x = 716.94

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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.