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Finding the Fourth Proportional to 221.85, 306.29 and 143.21

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Solution

The fourth proportional to 221.85, 306.29 and 143.21 is: 197.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.85 : 306.29 = 143.21 : x
  2. Step 2: Convert to fraction form
    221.85/306.29 = 143.21/x
  3. Step 3: Cross multiply
    221.85x = 306.29 × 143.21
  4. Step 4: Simplify right side
    221.85x = 43,864.91
  5. Step 5: Solve for x
    x = 43,864.91/221.85
  6. Step 6: Final answer
    x = 197.72

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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.