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Finding the Fourth Proportional to 20.87, 31.30 and 8.03

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Solution

The fourth proportional to 20.87, 31.30 and 8.03 is: 12.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.87 : 31.30 = 8.03 : x
  2. Step 2: Convert to fraction form
    20.87/31.30 = 8.03/x
  3. Step 3: Cross multiply
    20.87x = 31.30 × 8.03
  4. Step 4: Simplify right side
    20.87x = 251.34
  5. Step 5: Solve for x
    x = 251.34/20.87
  6. Step 6: Final answer
    x = 12.05

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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.