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Finding the Fourth Proportional to 71.86, 107.78 and 17.75

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Solution

The fourth proportional to 71.86, 107.78 and 17.75 is: 26.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.86 : 107.78 = 17.75 : x
  2. Step 2: Convert to fraction form
    71.86/107.78 = 17.75/x
  3. Step 3: Cross multiply
    71.86x = 107.78 × 17.75
  4. Step 4: Simplify right side
    71.86x = 1,913.41
  5. Step 5: Solve for x
    x = 1,913.41/71.86
  6. Step 6: Final answer
    x = 26.63

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.