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Finding the Fourth Proportional to 419.82, 629.47 and 145.80

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Solution

The fourth proportional to 419.82, 629.47 and 145.80 is: 218.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.82 : 629.47 = 145.80 : x
  2. Step 2: Convert to fraction form
    419.82/629.47 = 145.80/x
  3. Step 3: Cross multiply
    419.82x = 629.47 × 145.80
  4. Step 4: Simplify right side
    419.82x = 91,776.73
  5. Step 5: Solve for x
    x = 91,776.73/419.82
  6. Step 6: Final answer
    x = 218.61

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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.