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Finding the Fourth Proportional to 305.21, 421.16 and 180.82

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Solution

The fourth proportional to 305.21, 421.16 and 180.82 is: 249.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.21 : 421.16 = 180.82 : x
  2. Step 2: Convert to fraction form
    305.21/421.16 = 180.82/x
  3. Step 3: Cross multiply
    305.21x = 421.16 × 180.82
  4. Step 4: Simplify right side
    305.21x = 76,153.55
  5. Step 5: Solve for x
    x = 76,153.55/305.21
  6. Step 6: Final answer
    x = 249.52

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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.