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Finding the Fourth Proportional to 80.15, 111.35 and 79.40

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Solution

The fourth proportional to 80.15, 111.35 and 79.40 is: 110.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.15 : 111.35 = 79.40 : x
  2. Step 2: Convert to fraction form
    80.15/111.35 = 79.40/x
  3. Step 3: Cross multiply
    80.15x = 111.35 × 79.40
  4. Step 4: Simplify right side
    80.15x = 8,841.19
  5. Step 5: Solve for x
    x = 8,841.19/80.15
  6. Step 6: Final answer
    x = 110.31

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.