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Finding the Fourth Proportional to 399.33, 550.18 and 380.80

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Solution

The fourth proportional to 399.33, 550.18 and 380.80 is: 524.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.33 : 550.18 = 380.80 : x
  2. Step 2: Convert to fraction form
    399.33/550.18 = 380.80/x
  3. Step 3: Cross multiply
    399.33x = 550.18 × 380.80
  4. Step 4: Simplify right side
    399.33x = 209,503.89
  5. Step 5: Solve for x
    x = 209,503.89/399.33
  6. Step 6: Final answer
    x = 524.65

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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.