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Finding the Fourth Proportional to 7.89, 10.87 and 7.61

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Solution

The fourth proportional to 7.89, 10.87 and 7.61 is: 10.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.89 : 10.87 = 7.61 : x
  2. Step 2: Convert to fraction form
    7.89/10.87 = 7.61/x
  3. Step 3: Cross multiply
    7.89x = 10.87 × 7.61
  4. Step 4: Simplify right side
    7.89x = 82.72
  5. Step 5: Solve for x
    x = 82.72/7.89
  6. Step 6: Final answer
    x = 10.48

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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.