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Finding the Fourth Proportional to 34.80, 47.99 and 20.99

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Solution

The fourth proportional to 34.80, 47.99 and 20.99 is: 28.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    34.80 : 47.99 = 20.99 : x
  2. Step 2: Convert to fraction form
    34.80/47.99 = 20.99/x
  3. Step 3: Cross multiply
    34.80x = 47.99 × 20.99
  4. Step 4: Simplify right side
    34.80x = 1,007.31
  5. Step 5: Solve for x
    x = 1,007.31/34.80
  6. Step 6: Final answer
    x = 28.95

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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.