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Finding the Fourth Proportional to 12.80, 19.17 and 10.25

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Solution

The fourth proportional to 12.80, 19.17 and 10.25 is: 15.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.80 : 19.17 = 10.25 : x
  2. Step 2: Convert to fraction form
    12.80/19.17 = 10.25/x
  3. Step 3: Cross multiply
    12.80x = 19.17 × 10.25
  4. Step 4: Simplify right side
    12.80x = 196.44
  5. Step 5: Solve for x
    x = 196.44/12.80
  6. Step 6: Final answer
    x = 15.35

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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.