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Finding the Fourth Proportional to 638.18, 879.26 and 480.56

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Solution

The fourth proportional to 638.18, 879.26 and 480.56 is: 662.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.18 : 879.26 = 480.56 : x
  2. Step 2: Convert to fraction form
    638.18/879.26 = 480.56/x
  3. Step 3: Cross multiply
    638.18x = 879.26 × 480.56
  4. Step 4: Simplify right side
    638.18x = 422,537.19
  5. Step 5: Solve for x
    x = 422,537.19/638.18
  6. Step 6: Final answer
    x = 662.10

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Double scale
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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.