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Finding the Fourth Proportional to 221.96, 306.31 and 123.72

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Solution

The fourth proportional to 221.96, 306.31 and 123.72 is: 170.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.96 : 306.31 = 123.72 : x
  2. Step 2: Convert to fraction form
    221.96/306.31 = 123.72/x
  3. Step 3: Cross multiply
    221.96x = 306.31 × 123.72
  4. Step 4: Simplify right side
    221.96x = 37,894.52
  5. Step 5: Solve for x
    x = 37,894.52/221.96
  6. Step 6: Final answer
    x = 170.73

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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.