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Finding the Fourth Proportional to 629.56, 868.80 and 380.80

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Solution

The fourth proportional to 629.56, 868.80 and 380.80 is: 525.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.56 : 868.80 = 380.80 : x
  2. Step 2: Convert to fraction form
    629.56/868.80 = 380.80/x
  3. Step 3: Cross multiply
    629.56x = 868.80 × 380.80
  4. Step 4: Simplify right side
    629.56x = 330,839.04
  5. Step 5: Solve for x
    x = 330,839.04/629.56
  6. Step 6: Final answer
    x = 525.51

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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.