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Finding the Fourth Proportional to 28.30, 39 and 27.20

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Solution

The fourth proportional to 28.30, 39 and 27.20 is: 37.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.30 : 39 = 27.20 : x
  2. Step 2: Convert to fraction form
    28.30/39 = 27.20/x
  3. Step 3: Cross multiply
    28.30x = 39 × 27.20
  4. Step 4: Simplify right side
    28.30x = 1,060.80
  5. Step 5: Solve for x
    x = 1,060.80/28.30
  6. Step 6: Final answer
    x = 37.48

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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.