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Finding the Fourth Proportional to 6.80, 10.15 and 5.80

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Solution

The fourth proportional to 6.80, 10.15 and 5.80 is: 8.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.80 : 10.15 = 5.80 : x
  2. Step 2: Convert to fraction form
    6.80/10.15 = 5.80/x
  3. Step 3: Cross multiply
    6.80x = 10.15 × 5.80
  4. Step 4: Simplify right side
    6.80x = 58.87
  5. Step 5: Solve for x
    x = 58.87/6.80
  6. Step 6: Final answer
    x = 8.66

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.