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Finding the Fourth Proportional to 426.80, 636.78 and 380.60

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Solution

The fourth proportional to 426.80, 636.78 and 380.60 is: 567.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.80 : 636.78 = 380.60 : x
  2. Step 2: Convert to fraction form
    426.80/636.78 = 380.60/x
  3. Step 3: Cross multiply
    426.80x = 636.78 × 380.60
  4. Step 4: Simplify right side
    426.80x = 242,358.47
  5. Step 5: Solve for x
    x = 242,358.47/426.80
  6. Step 6: Final answer
    x = 567.85

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.