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Finding the Fourth Proportional to 789.40, 1,183.28 and 378.20

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Solution

The fourth proportional to 789.40, 1,183.28 and 378.20 is: 566.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    789.40 : 1,183.28 = 378.20 : x
  2. Step 2: Convert to fraction form
    789.40/1,183.28 = 378.20/x
  3. Step 3: Cross multiply
    789.40x = 1,183.28 × 378.20
  4. Step 4: Simplify right side
    789.40x = 447,516.50
  5. Step 5: Solve for x
    x = 447,516.50/789.40
  6. Step 6: Final answer
    x = 566.91

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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.