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Finding the Fourth Proportional to 638.20, 880.23 and 480.88

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Solution

The fourth proportional to 638.20, 880.23 and 480.88 is: 663.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.20 : 880.23 = 480.88 : x
  2. Step 2: Convert to fraction form
    638.20/880.23 = 480.88/x
  3. Step 3: Cross multiply
    638.20x = 880.23 × 480.88
  4. Step 4: Simplify right side
    638.20x = 423,285.00
  5. Step 5: Solve for x
    x = 423,285.00/638.20
  6. Step 6: Final answer
    x = 663.25

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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.