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Finding the Fourth Proportional to 40.83, 61.21 and 20.53

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Solution

The fourth proportional to 40.83, 61.21 and 20.53 is: 30.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.83 : 61.21 = 20.53 : x
  2. Step 2: Convert to fraction form
    40.83/61.21 = 20.53/x
  3. Step 3: Cross multiply
    40.83x = 61.21 × 20.53
  4. Step 4: Simplify right side
    40.83x = 1,256.64
  5. Step 5: Solve for x
    x = 1,256.64/40.83
  6. Step 6: Final answer
    x = 30.78

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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.