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Finding the Fourth Proportional to 399.49, 550.65 and 306.07

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Solution

The fourth proportional to 399.49, 550.65 and 306.07 is: 421.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.49 : 550.65 = 306.07 : x
  2. Step 2: Convert to fraction form
    399.49/550.65 = 306.07/x
  3. Step 3: Cross multiply
    399.49x = 550.65 × 306.07
  4. Step 4: Simplify right side
    399.49x = 168,537.45
  5. Step 5: Solve for x
    x = 168,537.45/399.49
  6. Step 6: Final answer
    x = 421.88

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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.