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Finding the Fourth Proportional to 80.80, 111.38 and 74.72

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Solution

The fourth proportional to 80.80, 111.38 and 74.72 is: 103.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.80 : 111.38 = 74.72 : x
  2. Step 2: Convert to fraction form
    80.80/111.38 = 74.72/x
  3. Step 3: Cross multiply
    80.80x = 111.38 × 74.72
  4. Step 4: Simplify right side
    80.80x = 8,322.22
  5. Step 5: Solve for x
    x = 8,322.22/80.80
  6. Step 6: Final answer
    x = 103.00

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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.