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Finding the Fourth Proportional to 378.60, 567.90 and 205.80

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Solution

The fourth proportional to 378.60, 567.90 and 205.80 is: 308.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.60 : 567.90 = 205.80 : x
  2. Step 2: Convert to fraction form
    378.60/567.90 = 205.80/x
  3. Step 3: Cross multiply
    378.60x = 567.90 × 205.80
  4. Step 4: Simplify right side
    378.60x = 116,873.82
  5. Step 5: Solve for x
    x = 116,873.82/378.60
  6. Step 6: Final answer
    x = 308.70

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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.