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Finding the Fourth Proportional to 638.18, 880.62 and 416.78

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Solution

The fourth proportional to 638.18, 880.62 and 416.78 is: 575.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.18 : 880.62 = 416.78 : x
  2. Step 2: Convert to fraction form
    638.18/880.62 = 416.78/x
  3. Step 3: Cross multiply
    638.18x = 880.62 × 416.78
  4. Step 4: Simplify right side
    638.18x = 367,024.80
  5. Step 5: Solve for x
    x = 367,024.80/638.18
  6. Step 6: Final answer
    x = 575.11

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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.