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Finding the Fourth Proportional to 638.74, 958.38 and 254.26

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Solution

The fourth proportional to 638.74, 958.38 and 254.26 is: 381.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.74 : 958.38 = 254.26 : x
  2. Step 2: Convert to fraction form
    638.74/958.38 = 254.26/x
  3. Step 3: Cross multiply
    638.74x = 958.38 × 254.26
  4. Step 4: Simplify right side
    638.74x = 243,677.70
  5. Step 5: Solve for x
    x = 243,677.70/638.74
  6. Step 6: Final answer
    x = 381.50

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Half scale
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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 (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.