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Finding the Fourth Proportional to 13.38, 20 and 12.18

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Solution

The fourth proportional to 13.38, 20 and 12.18 is: 18.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.38 : 20 = 12.18 : x
  2. Step 2: Convert to fraction form
    13.38/20 = 12.18/x
  3. Step 3: Cross multiply
    13.38x = 20 × 12.18
  4. Step 4: Simplify right side
    13.38x = 243.60
  5. Step 5: Solve for x
    x = 243.60/13.38
  6. Step 6: Final answer
    x = 18.21

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1.5x scale

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.