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Finding the Fourth Proportional to 411.02, 615.90 and 205.39

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Solution

The fourth proportional to 411.02, 615.90 and 205.39 is: 307.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    411.02 : 615.90 = 205.39 : x
  2. Step 2: Convert to fraction form
    411.02/615.90 = 205.39/x
  3. Step 3: Cross multiply
    411.02x = 615.90 × 205.39
  4. Step 4: Simplify right side
    411.02x = 126,497.78
  5. Step 5: Solve for x
    x = 126,497.78/411.02
  6. Step 6: Final answer
    x = 307.76

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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.