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Finding the Fourth Proportional to 12.80, 17.60 and 11.18

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Solution

The fourth proportional to 12.80, 17.60 and 11.18 is: 15.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.80 : 17.60 = 11.18 : x
  2. Step 2: Convert to fraction form
    12.80/17.60 = 11.18/x
  3. Step 3: Cross multiply
    12.80x = 17.60 × 11.18
  4. Step 4: Simplify right side
    12.80x = 196.77
  5. Step 5: Solve for x
    x = 196.77/12.80
  6. Step 6: Final answer
    x = 15.37

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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.