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Finding the Fourth Proportional to 638.26, 879.99 and 520.10

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Solution

The fourth proportional to 638.26, 879.99 and 520.10 is: 717.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.26 : 879.99 = 520.10 : x
  2. Step 2: Convert to fraction form
    638.26/879.99 = 520.10/x
  3. Step 3: Cross multiply
    638.26x = 879.99 × 520.10
  4. Step 4: Simplify right side
    638.26x = 457,686.16
  5. Step 5: Solve for x
    x = 457,686.16/638.26
  6. Step 6: Final answer
    x = 717.08

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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.