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Finding the Fourth Proportional to 419.90, 629.91 and 185.90

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Solution

The fourth proportional to 419.90, 629.91 and 185.90 is: 278.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.90 : 629.91 = 185.90 : x
  2. Step 2: Convert to fraction form
    419.90/629.91 = 185.90/x
  3. Step 3: Cross multiply
    419.90x = 629.91 × 185.90
  4. Step 4: Simplify right side
    419.90x = 117,100.27
  5. Step 5: Solve for x
    x = 117,100.27/419.90
  6. Step 6: Final answer
    x = 278.88

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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.