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Finding the Fourth Proportional to 6.80, 10.18 and 5.11

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Solution

The fourth proportional to 6.80, 10.18 and 5.11 is: 7.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.80 : 10.18 = 5.11 : x
  2. Step 2: Convert to fraction form
    6.80/10.18 = 5.11/x
  3. Step 3: Cross multiply
    6.80x = 10.18 × 5.11
  4. Step 4: Simplify right side
    6.80x = 52.02
  5. Step 5: Solve for x
    x = 52.02/6.80
  6. Step 6: Final answer
    x = 7.65

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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.