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Finding the Fourth Proportional to 305.39, 421.31 and 181.06

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Solution

The fourth proportional to 305.39, 421.31 and 181.06 is: 249.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.39 : 421.31 = 181.06 : x
  2. Step 2: Convert to fraction form
    305.39/421.31 = 181.06/x
  3. Step 3: Cross multiply
    305.39x = 421.31 × 181.06
  4. Step 4: Simplify right side
    305.39x = 76,280.43
  5. Step 5: Solve for x
    x = 76,280.43/305.39
  6. Step 6: Final answer
    x = 249.78

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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.