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Finding the Fourth Proportional to 34.54, 51.78 and 20.80

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Solution

The fourth proportional to 34.54, 51.78 and 20.80 is: 31.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    34.54 : 51.78 = 20.80 : x
  2. Step 2: Convert to fraction form
    34.54/51.78 = 20.80/x
  3. Step 3: Cross multiply
    34.54x = 51.78 × 20.80
  4. Step 4: Simplify right side
    34.54x = 1,077.02
  5. Step 5: Solve for x
    x = 1,077.02/34.54
  6. Step 6: Final answer
    x = 31.18

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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.