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Finding the Fourth Proportional to 806.30, 1,209.38 and 221.30

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Solution

The fourth proportional to 806.30, 1,209.38 and 221.30 is: 331.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.30 : 1,209.38 = 221.30 : x
  2. Step 2: Convert to fraction form
    806.30/1,209.38 = 221.30/x
  3. Step 3: Cross multiply
    806.30x = 1,209.38 × 221.30
  4. Step 4: Simplify right side
    806.30x = 267,635.79
  5. Step 5: Solve for x
    x = 267,635.79/806.30
  6. Step 6: Final answer
    x = 331.93

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.