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Finding the Fourth Proportional to 12.75, 17.59 and 7.89

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Solution

The fourth proportional to 12.75, 17.59 and 7.89 is: 10.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.75 : 17.59 = 7.89 : x
  2. Step 2: Convert to fraction form
    12.75/17.59 = 7.89/x
  3. Step 3: Cross multiply
    12.75x = 17.59 × 7.89
  4. Step 4: Simplify right side
    12.75x = 138.79
  5. Step 5: Solve for x
    x = 138.79/12.75
  6. Step 6: Final answer
    x = 10.89

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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.