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Finding the Fourth Proportional to 40.43, 55.81 and 28.21

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Solution

The fourth proportional to 40.43, 55.81 and 28.21 is: 38.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.43 : 55.81 = 28.21 : x
  2. Step 2: Convert to fraction form
    40.43/55.81 = 28.21/x
  3. Step 3: Cross multiply
    40.43x = 55.81 × 28.21
  4. Step 4: Simplify right side
    40.43x = 1,574.24
  5. Step 5: Solve for x
    x = 1,574.24/40.43
  6. Step 6: Final answer
    x = 38.94

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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.