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Finding the Fourth Proportional to 10, 13.80 and 8.80

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Solution

The fourth proportional to 10, 13.80 and 8.80 is: 12.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    10 : 13.80 = 8.80 : x
  2. Step 2: Convert to fraction form
    10/13.80 = 8.80/x
  3. Step 3: Cross multiply
    10x = 13.80 × 8.80
  4. Step 4: Simplify right side
    10x = 121.44
  5. Step 5: Solve for x
    x = 121.44/10
  6. Step 6: Final answer
    x = 12.14

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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.