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Finding the Fourth Proportional to 13.79, 20.79 and 13.23

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Solution

The fourth proportional to 13.79, 20.79 and 13.23 is: 19.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.79 : 20.79 = 13.23 : x
  2. Step 2: Convert to fraction form
    13.79/20.79 = 13.23/x
  3. Step 3: Cross multiply
    13.79x = 20.79 × 13.23
  4. Step 4: Simplify right side
    13.79x = 275.05
  5. Step 5: Solve for x
    x = 275.05/13.79
  6. Step 6: Final answer
    x = 19.94

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.