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Finding the Fourth Proportional to 620.72, 931.31 and 255.75

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Solution

The fourth proportional to 620.72, 931.31 and 255.75 is: 383.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.72 : 931.31 = 255.75 : x
  2. Step 2: Convert to fraction form
    620.72/931.31 = 255.75/x
  3. Step 3: Cross multiply
    620.72x = 931.31 × 255.75
  4. Step 4: Simplify right side
    620.72x = 238,182.53
  5. Step 5: Solve for x
    x = 238,182.53/620.72
  6. Step 6: Final answer
    x = 383.72

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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.