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Finding the Fourth Proportional to 18.90, 28.30 and 16.75

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Solution

The fourth proportional to 18.90, 28.30 and 16.75 is: 25.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.90 : 28.30 = 16.75 : x
  2. Step 2: Convert to fraction form
    18.90/28.30 = 16.75/x
  3. Step 3: Cross multiply
    18.90x = 28.30 × 16.75
  4. Step 4: Simplify right side
    18.90x = 474.03
  5. Step 5: Solve for x
    x = 474.03/18.90
  6. Step 6: Final answer
    x = 25.08

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.