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Finding the Fourth Proportional to 206.87, 310.19 and 129.60

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Solution

The fourth proportional to 206.87, 310.19 and 129.60 is: 194.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.87 : 310.19 = 129.60 : x
  2. Step 2: Convert to fraction form
    206.87/310.19 = 129.60/x
  3. Step 3: Cross multiply
    206.87x = 310.19 × 129.60
  4. Step 4: Simplify right side
    206.87x = 40,199.98
  5. Step 5: Solve for x
    x = 40,199.98/206.87
  6. Step 6: Final answer
    x = 194.33

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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.