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Finding the Fourth Proportional to 36.80, 54.91 and 30.80

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Solution

The fourth proportional to 36.80, 54.91 and 30.80 is: 45.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    36.80 : 54.91 = 30.80 : x
  2. Step 2: Convert to fraction form
    36.80/54.91 = 30.80/x
  3. Step 3: Cross multiply
    36.80x = 54.91 × 30.80
  4. Step 4: Simplify right side
    36.80x = 1,691.23
  5. Step 5: Solve for x
    x = 1,691.23/36.80
  6. Step 6: Final answer
    x = 45.96

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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.