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Finding the Fourth Proportional to 305.87, 421.49 and 218.39

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Solution

The fourth proportional to 305.87, 421.49 and 218.39 is: 300.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.87 : 421.49 = 218.39 : x
  2. Step 2: Convert to fraction form
    305.87/421.49 = 218.39/x
  3. Step 3: Cross multiply
    305.87x = 421.49 × 218.39
  4. Step 4: Simplify right side
    305.87x = 92,048.11
  5. Step 5: Solve for x
    x = 92,048.11/305.87
  6. Step 6: Final answer
    x = 300.94

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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.