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Finding the Fourth Proportional to 309.92, 428.28 and 227.12

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Solution

The fourth proportional to 309.92, 428.28 and 227.12 is: 313.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.92 : 428.28 = 227.12 : x
  2. Step 2: Convert to fraction form
    309.92/428.28 = 227.12/x
  3. Step 3: Cross multiply
    309.92x = 428.28 × 227.12
  4. Step 4: Simplify right side
    309.92x = 97,270.95
  5. Step 5: Solve for x
    x = 97,270.95/309.92
  6. Step 6: Final answer
    x = 313.86

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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.