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Finding the Fourth Proportional to 19.40, 28.91 and 18.55

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Solution

The fourth proportional to 19.40, 28.91 and 18.55 is: 27.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.40 : 28.91 = 18.55 : x
  2. Step 2: Convert to fraction form
    19.40/28.91 = 18.55/x
  3. Step 3: Cross multiply
    19.40x = 28.91 × 18.55
  4. Step 4: Simplify right side
    19.40x = 536.33
  5. Step 5: Solve for x
    x = 536.33/19.40
  6. Step 6: Final answer
    x = 27.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.