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Finding the Fourth Proportional to 28.31, 42.21 and 26.66

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Solution

The fourth proportional to 28.31, 42.21 and 26.66 is: 39.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.31 : 42.21 = 26.66 : x
  2. Step 2: Convert to fraction form
    28.31/42.21 = 26.66/x
  3. Step 3: Cross multiply
    28.31x = 42.21 × 26.66
  4. Step 4: Simplify right side
    28.31x = 1,125.42
  5. Step 5: Solve for x
    x = 1,125.42/28.31
  6. Step 6: Final answer
    x = 39.76

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.