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Finding the Fourth Proportional to 399.45, 550.79 and 320.51

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Solution

The fourth proportional to 399.45, 550.79 and 320.51 is: 441.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.45 : 550.79 = 320.51 : x
  2. Step 2: Convert to fraction form
    399.45/550.79 = 320.51/x
  3. Step 3: Cross multiply
    399.45x = 550.79 × 320.51
  4. Step 4: Simplify right side
    399.45x = 176,534.68
  5. Step 5: Solve for x
    x = 176,534.68/399.45
  6. Step 6: Final answer
    x = 441.94

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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.