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Finding the Fourth Proportional to 609.12, 913.91 and 219.15

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Solution

The fourth proportional to 609.12, 913.91 and 219.15 is: 328.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.12 : 913.91 = 219.15 : x
  2. Step 2: Convert to fraction form
    609.12/913.91 = 219.15/x
  3. Step 3: Cross multiply
    609.12x = 913.91 × 219.15
  4. Step 4: Simplify right side
    609.12x = 200,282.28
  5. Step 5: Solve for x
    x = 200,282.28/609.12
  6. Step 6: Final answer
    x = 328.81

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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.