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Finding the Fourth Proportional to 419.32, 629.10 and 130.78

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Solution

The fourth proportional to 419.32, 629.10 and 130.78 is: 196.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.32 : 629.10 = 130.78 : x
  2. Step 2: Convert to fraction form
    419.32/629.10 = 130.78/x
  3. Step 3: Cross multiply
    419.32x = 629.10 × 130.78
  4. Step 4: Simplify right side
    419.32x = 82,273.70
  5. Step 5: Solve for x
    x = 82,273.70/419.32
  6. Step 6: Final answer
    x = 196.21

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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.