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Finding the Fourth Proportional to 638.33, 880.20 and 491.31

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Solution

The fourth proportional to 638.33, 880.20 and 491.31 is: 677.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.33 : 880.20 = 491.31 : x
  2. Step 2: Convert to fraction form
    638.33/880.20 = 491.31/x
  3. Step 3: Cross multiply
    638.33x = 880.20 × 491.31
  4. Step 4: Simplify right side
    638.33x = 432,451.06
  5. Step 5: Solve for x
    x = 432,451.06/638.33
  6. Step 6: Final answer
    x = 677.48

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Double scale
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Similar ratio
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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.