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Finding the Fourth Proportional to 609.09, 839.98 and 399.45

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Solution

The fourth proportional to 609.09, 839.98 and 399.45 is: 550.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.09 : 839.98 = 399.45 : x
  2. Step 2: Convert to fraction form
    609.09/839.98 = 399.45/x
  3. Step 3: Cross multiply
    609.09x = 839.98 × 399.45
  4. Step 4: Simplify right side
    609.09x = 335,530.01
  5. Step 5: Solve for x
    x = 335,530.01/609.09
  6. Step 6: Final answer
    x = 550.87

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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.