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Finding the Fourth Proportional to 410.85, 615.80 and 205.56

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Solution

The fourth proportional to 410.85, 615.80 and 205.56 is: 308.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.85 : 615.80 = 205.56 : x
  2. Step 2: Convert to fraction form
    410.85/615.80 = 205.56/x
  3. Step 3: Cross multiply
    410.85x = 615.80 × 205.56
  4. Step 4: Simplify right side
    410.85x = 126,584.36
  5. Step 5: Solve for x
    x = 126,584.36/410.85
  6. Step 6: Final answer
    x = 308.10

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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.