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Finding the Fourth Proportional to 19.80, 27.38 and 19.20

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Solution

The fourth proportional to 19.80, 27.38 and 19.20 is: 26.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.80 : 27.38 = 19.20 : x
  2. Step 2: Convert to fraction form
    19.80/27.38 = 19.20/x
  3. Step 3: Cross multiply
    19.80x = 27.38 × 19.20
  4. Step 4: Simplify right side
    19.80x = 525.70
  5. Step 5: Solve for x
    x = 525.70/19.80
  6. Step 6: Final answer
    x = 26.55

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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.