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Finding the Fourth Proportional to 20.05, 30.04 and 17.80

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Solution

The fourth proportional to 20.05, 30.04 and 17.80 is: 26.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.05 : 30.04 = 17.80 : x
  2. Step 2: Convert to fraction form
    20.05/30.04 = 17.80/x
  3. Step 3: Cross multiply
    20.05x = 30.04 × 17.80
  4. Step 4: Simplify right side
    20.05x = 534.71
  5. Step 5: Solve for x
    x = 534.71/20.05
  6. Step 6: Final answer
    x = 26.67

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.