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Finding the Fourth Proportional to 629.80, 869.36 and 397.08

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Solution

The fourth proportional to 629.80, 869.36 and 397.08 is: 548.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.80 : 869.36 = 397.08 : x
  2. Step 2: Convert to fraction form
    629.80/869.36 = 397.08/x
  3. Step 3: Cross multiply
    629.80x = 869.36 × 397.08
  4. Step 4: Simplify right side
    629.80x = 345,205.47
  5. Step 5: Solve for x
    x = 345,205.47/629.80
  6. Step 6: Final answer
    x = 548.12

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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.