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Finding the Fourth Proportional to 20.20, 30.19 and 15.64

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Solution

The fourth proportional to 20.20, 30.19 and 15.64 is: 23.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.20 : 30.19 = 15.64 : x
  2. Step 2: Convert to fraction form
    20.20/30.19 = 15.64/x
  3. Step 3: Cross multiply
    20.20x = 30.19 × 15.64
  4. Step 4: Simplify right side
    20.20x = 472.17
  5. Step 5: Solve for x
    x = 472.17/20.20
  6. Step 6: Final answer
    x = 23.37

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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.