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Finding the Fourth Proportional to 40.05, 55.19 and 30.83

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Solution

The fourth proportional to 40.05, 55.19 and 30.83 is: 42.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.05 : 55.19 = 30.83 : x
  2. Step 2: Convert to fraction form
    40.05/55.19 = 30.83/x
  3. Step 3: Cross multiply
    40.05x = 55.19 × 30.83
  4. Step 4: Simplify right side
    40.05x = 1,701.31
  5. Step 5: Solve for x
    x = 1,701.31/40.05
  6. Step 6: Final answer
    x = 42.48

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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.