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Finding the Fourth Proportional to 371.22, 512.28 and 221.78

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Solution

The fourth proportional to 371.22, 512.28 and 221.78 is: 306.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    371.22 : 512.28 = 221.78 : x
  2. Step 2: Convert to fraction form
    371.22/512.28 = 221.78/x
  3. Step 3: Cross multiply
    371.22x = 512.28 × 221.78
  4. Step 4: Simplify right side
    371.22x = 113,610.90
  5. Step 5: Solve for x
    x = 113,610.90/371.22
  6. Step 6: Final answer
    x = 306.05

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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.