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Finding the Fourth Proportional to 638.10, 956.40 and 378.22

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Solution

The fourth proportional to 638.10, 956.40 and 378.22 is: 566.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.10 : 956.40 = 378.22 : x
  2. Step 2: Convert to fraction form
    638.10/956.40 = 378.22/x
  3. Step 3: Cross multiply
    638.10x = 956.40 × 378.22
  4. Step 4: Simplify right side
    638.10x = 361,729.61
  5. Step 5: Solve for x
    x = 361,729.61/638.10
  6. Step 6: Final answer
    x = 566.89

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Double scale
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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.