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Finding the Fourth Proportional to 221.45, 305.47 and 205.81

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Solution

The fourth proportional to 221.45, 305.47 and 205.81 is: 283.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.45 : 305.47 = 205.81 : x
  2. Step 2: Convert to fraction form
    221.45/305.47 = 205.81/x
  3. Step 3: Cross multiply
    221.45x = 305.47 × 205.81
  4. Step 4: Simplify right side
    221.45x = 62,868.27
  5. Step 5: Solve for x
    x = 62,868.27/221.45
  6. Step 6: Final answer
    x = 283.90

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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.