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Finding the Fourth Proportional to 20.57, 30.69 and 18.29

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Solution

The fourth proportional to 20.57, 30.69 and 18.29 is: 27.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.57 : 30.69 = 18.29 : x
  2. Step 2: Convert to fraction form
    20.57/30.69 = 18.29/x
  3. Step 3: Cross multiply
    20.57x = 30.69 × 18.29
  4. Step 4: Simplify right side
    20.57x = 561.40
  5. Step 5: Solve for x
    x = 561.40/20.57
  6. Step 6: Final answer
    x = 27.30

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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.