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Finding the Fourth Proportional to 309.96, 428.26 and 245

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Solution

The fourth proportional to 309.96, 428.26 and 245 is: 338.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.96 : 428.26 = 245 : x
  2. Step 2: Convert to fraction form
    309.96/428.26 = 245/x
  3. Step 3: Cross multiply
    309.96x = 428.26 × 245
  4. Step 4: Simplify right side
    309.96x = 104,923.70
  5. Step 5: Solve for x
    x = 104,923.70/309.96
  6. Step 6: Final answer
    x = 338.51

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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.