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Finding the Fourth Proportional to 221.05, 305.20 and 202.56

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Solution

The fourth proportional to 221.05, 305.20 and 202.56 is: 279.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.05 : 305.20 = 202.56 : x
  2. Step 2: Convert to fraction form
    221.05/305.20 = 202.56/x
  3. Step 3: Cross multiply
    221.05x = 305.20 × 202.56
  4. Step 4: Simplify right side
    221.05x = 61,821.31
  5. Step 5: Solve for x
    x = 61,821.31/221.05
  6. Step 6: Final answer
    x = 279.67

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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.