Home / 30.20-41.67-28.85

Finding the Fourth Proportional to 30.20, 41.67 and 28.85

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Solution

The fourth proportional to 30.20, 41.67 and 28.85 is: 39.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.20 : 41.67 = 28.85 : x
  2. Step 2: Convert to fraction form
    30.20/41.67 = 28.85/x
  3. Step 3: Cross multiply
    30.20x = 41.67 × 28.85
  4. Step 4: Simplify right side
    30.20x = 1,201.97
  5. Step 5: Solve for x
    x = 1,201.97/30.20
  6. Step 6: Final answer
    x = 39.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.