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Finding the Fourth Proportional to 51.75, 71.42 and 28.75

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Solution

The fourth proportional to 51.75, 71.42 and 28.75 is: 39.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.75 : 71.42 = 28.75 : x
  2. Step 2: Convert to fraction form
    51.75/71.42 = 28.75/x
  3. Step 3: Cross multiply
    51.75x = 71.42 × 28.75
  4. Step 4: Simplify right side
    51.75x = 2,053.33
  5. Step 5: Solve for x
    x = 2,053.33/51.75
  6. Step 6: Final answer
    x = 39.68

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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.