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Finding the Fourth Proportional to 18.38, 25.35 and 15.31

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Solution

The fourth proportional to 18.38, 25.35 and 15.31 is: 21.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.38 : 25.35 = 15.31 : x
  2. Step 2: Convert to fraction form
    18.38/25.35 = 15.31/x
  3. Step 3: Cross multiply
    18.38x = 25.35 × 15.31
  4. Step 4: Simplify right side
    18.38x = 388.03
  5. Step 5: Solve for x
    x = 388.03/18.38
  6. Step 6: Final answer
    x = 21.11

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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.