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Finding the Fourth Proportional to 28.78, 43.38 and 27.88

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Solution

The fourth proportional to 28.78, 43.38 and 27.88 is: 42.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.78 : 43.38 = 27.88 : x
  2. Step 2: Convert to fraction form
    28.78/43.38 = 27.88/x
  3. Step 3: Cross multiply
    28.78x = 43.38 × 27.88
  4. Step 4: Simplify right side
    28.78x = 1,209.43
  5. Step 5: Solve for x
    x = 1,209.43/28.78
  6. Step 6: Final answer
    x = 42.02

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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.