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Finding the Fourth Proportional to 13.26, 18.31 and 8.90

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Solution

The fourth proportional to 13.26, 18.31 and 8.90 is: 12.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.26 : 18.31 = 8.90 : x
  2. Step 2: Convert to fraction form
    13.26/18.31 = 8.90/x
  3. Step 3: Cross multiply
    13.26x = 18.31 × 8.90
  4. Step 4: Simplify right side
    13.26x = 162.93
  5. Step 5: Solve for x
    x = 162.93/13.26
  6. Step 6: Final answer
    x = 12.28

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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.