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Finding the Fourth Proportional to 8.79, 12.12 and 5.55

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Solution

The fourth proportional to 8.79, 12.12 and 5.55 is: 7.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.79 : 12.12 = 5.55 : x
  2. Step 2: Convert to fraction form
    8.79/12.12 = 5.55/x
  3. Step 3: Cross multiply
    8.79x = 12.12 × 5.55
  4. Step 4: Simplify right side
    8.79x = 67.27
  5. Step 5: Solve for x
    x = 67.27/8.79
  6. Step 6: Final answer
    x = 7.65

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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.