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Finding the Fourth Proportional to 419.66, 629.78 and 145.75

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Solution

The fourth proportional to 419.66, 629.78 and 145.75 is: 218.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.66 : 629.78 = 145.75 : x
  2. Step 2: Convert to fraction form
    419.66/629.78 = 145.75/x
  3. Step 3: Cross multiply
    419.66x = 629.78 × 145.75
  4. Step 4: Simplify right side
    419.66x = 91,789.31
  5. Step 5: Solve for x
    x = 91,789.31/419.66
  6. Step 6: Final answer
    x = 218.73

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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.