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Finding the Fourth Proportional to 419.34, 629.05 and 130.78

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Solution

The fourth proportional to 419.34, 629.05 and 130.78 is: 196.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.34 : 629.05 = 130.78 : x
  2. Step 2: Convert to fraction form
    419.34/629.05 = 130.78/x
  3. Step 3: Cross multiply
    419.34x = 629.05 × 130.78
  4. Step 4: Simplify right side
    419.34x = 82,267.86
  5. Step 5: Solve for x
    x = 82,267.86/419.34
  6. Step 6: Final answer
    x = 196.18

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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.