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Finding the Fourth Proportional to 378.90, 568.68 and 205.74

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Solution

The fourth proportional to 378.90, 568.68 and 205.74 is: 308.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.90 : 568.68 = 205.74 : x
  2. Step 2: Convert to fraction form
    378.90/568.68 = 205.74/x
  3. Step 3: Cross multiply
    378.90x = 568.68 × 205.74
  4. Step 4: Simplify right side
    378.90x = 117,000.22
  5. Step 5: Solve for x
    x = 117,000.22/378.90
  6. Step 6: Final answer
    x = 308.79

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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.