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Finding the Fourth Proportional to 843.80, 1,265.10 and 381.20

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Solution

The fourth proportional to 843.80, 1,265.10 and 381.20 is: 571.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    843.80 : 1,265.10 = 381.20 : x
  2. Step 2: Convert to fraction form
    843.80/1,265.10 = 381.20/x
  3. Step 3: Cross multiply
    843.80x = 1,265.10 × 381.20
  4. Step 4: Simplify right side
    843.80x = 482,256.12
  5. Step 5: Solve for x
    x = 482,256.12/843.80
  6. Step 6: Final answer
    x = 571.53

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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.