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Finding the Fourth Proportional to 8.12, 11.20 and 5.05

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Solution

The fourth proportional to 8.12, 11.20 and 5.05 is: 6.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.12 : 11.20 = 5.05 : x
  2. Step 2: Convert to fraction form
    8.12/11.20 = 5.05/x
  3. Step 3: Cross multiply
    8.12x = 11.20 × 5.05
  4. Step 4: Simplify right side
    8.12x = 56.56
  5. Step 5: Solve for x
    x = 56.56/8.12
  6. Step 6: Final answer
    x = 6.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.