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Finding the Fourth Proportional to 206.80, 309.98 and 103.88

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Solution

The fourth proportional to 206.80, 309.98 and 103.88 is: 155.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.80 : 309.98 = 103.88 : x
  2. Step 2: Convert to fraction form
    206.80/309.98 = 103.88/x
  3. Step 3: Cross multiply
    206.80x = 309.98 × 103.88
  4. Step 4: Simplify right side
    206.80x = 32,200.72
  5. Step 5: Solve for x
    x = 32,200.72/206.80
  6. Step 6: Final answer
    x = 155.71

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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.