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Finding the Fourth Proportional to 80.16, 111.40 and 79.28

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Solution

The fourth proportional to 80.16, 111.40 and 79.28 is: 110.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.16 : 111.40 = 79.28 : x
  2. Step 2: Convert to fraction form
    80.16/111.40 = 79.28/x
  3. Step 3: Cross multiply
    80.16x = 111.40 × 79.28
  4. Step 4: Simplify right side
    80.16x = 8,831.79
  5. Step 5: Solve for x
    x = 8,831.79/80.16
  6. Step 6: Final answer
    x = 110.18

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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.