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Finding the Fourth Proportional to 28.61, 43.15 and 28.31

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Solution

The fourth proportional to 28.61, 43.15 and 28.31 is: 42.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.61 : 43.15 = 28.31 : x
  2. Step 2: Convert to fraction form
    28.61/43.15 = 28.31/x
  3. Step 3: Cross multiply
    28.61x = 43.15 × 28.31
  4. Step 4: Simplify right side
    28.61x = 1,221.29
  5. Step 5: Solve for x
    x = 1,221.29/28.61
  6. Step 6: Final answer
    x = 42.69

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.