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Finding the Fourth Proportional to 79.76, 120.20 and 67.88

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Solution

The fourth proportional to 79.76, 120.20 and 67.88 is: 102.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.76 : 120.20 = 67.88 : x
  2. Step 2: Convert to fraction form
    79.76/120.20 = 67.88/x
  3. Step 3: Cross multiply
    79.76x = 120.20 × 67.88
  4. Step 4: Simplify right side
    79.76x = 8,159.18
  5. Step 5: Solve for x
    x = 8,159.18/79.76
  6. Step 6: Final answer
    x = 102.30

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.