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Finding the Fourth Proportional to 8.41, 12.61 and 7.78

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Solution

The fourth proportional to 8.41, 12.61 and 7.78 is: 11.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.41 : 12.61 = 7.78 : x
  2. Step 2: Convert to fraction form
    8.41/12.61 = 7.78/x
  3. Step 3: Cross multiply
    8.41x = 12.61 × 7.78
  4. Step 4: Simplify right side
    8.41x = 98.02
  5. Step 5: Solve for x
    x = 98.02/8.41
  6. Step 6: Final answer
    x = 11.65

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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.