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Finding the Fourth Proportional to 28.08, 42.20 and 27.20

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Solution

The fourth proportional to 28.08, 42.20 and 27.20 is: 40.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.08 : 42.20 = 27.20 : x
  2. Step 2: Convert to fraction form
    28.08/42.20 = 27.20/x
  3. Step 3: Cross multiply
    28.08x = 42.20 × 27.20
  4. Step 4: Simplify right side
    28.08x = 1,147.84
  5. Step 5: Solve for x
    x = 1,147.84/28.08
  6. Step 6: Final answer
    x = 40.88

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.