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Finding the Fourth Proportional to 638.62, 880.80 and 481.78

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Solution

The fourth proportional to 638.62, 880.80 and 481.78 is: 664.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.62 : 880.80 = 481.78 : x
  2. Step 2: Convert to fraction form
    638.62/880.80 = 481.78/x
  3. Step 3: Cross multiply
    638.62x = 880.80 × 481.78
  4. Step 4: Simplify right side
    638.62x = 424,351.82
  5. Step 5: Solve for x
    x = 424,351.82/638.62
  6. Step 6: Final answer
    x = 664.48

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1.5x scale

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.