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Finding the Fourth Proportional to 18.90, 28.18 and 18.34

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Solution

The fourth proportional to 18.90, 28.18 and 18.34 is: 27.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.90 : 28.18 = 18.34 : x
  2. Step 2: Convert to fraction form
    18.90/28.18 = 18.34/x
  3. Step 3: Cross multiply
    18.90x = 28.18 × 18.34
  4. Step 4: Simplify right side
    18.90x = 516.93
  5. Step 5: Solve for x
    x = 516.93/18.90
  6. Step 6: Final answer
    x = 27.35

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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.