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Finding the Fourth Proportional to 40.82, 61.20 and 20.51

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Solution

The fourth proportional to 40.82, 61.20 and 20.51 is: 30.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.82 : 61.20 = 20.51 : x
  2. Step 2: Convert to fraction form
    40.82/61.20 = 20.51/x
  3. Step 3: Cross multiply
    40.82x = 61.20 × 20.51
  4. Step 4: Simplify right side
    40.82x = 1,255.21
  5. Step 5: Solve for x
    x = 1,255.21/40.82
  6. Step 6: Final answer
    x = 30.75

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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.