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Finding the Fourth Proportional to 80.32, 121.09 and 79.63

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Solution

The fourth proportional to 80.32, 121.09 and 79.63 is: 120.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.32 : 121.09 = 79.63 : x
  2. Step 2: Convert to fraction form
    80.32/121.09 = 79.63/x
  3. Step 3: Cross multiply
    80.32x = 121.09 × 79.63
  4. Step 4: Simplify right side
    80.32x = 9,642.40
  5. Step 5: Solve for x
    x = 9,642.40/80.32
  6. Step 6: Final answer
    x = 120.05

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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.