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Finding the Fourth Proportional to 221.63, 330.98 and 209.79

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Solution

The fourth proportional to 221.63, 330.98 and 209.79 is: 313.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.63 : 330.98 = 209.79 : x
  2. Step 2: Convert to fraction form
    221.63/330.98 = 209.79/x
  3. Step 3: Cross multiply
    221.63x = 330.98 × 209.79
  4. Step 4: Simplify right side
    221.63x = 69,435.25
  5. Step 5: Solve for x
    x = 69,435.25/221.63
  6. Step 6: Final answer
    x = 313.30

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.