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Finding the Fourth Proportional to 419.87, 629.39 and 203.60

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Solution

The fourth proportional to 419.87, 629.39 and 203.60 is: 305.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.87 : 629.39 = 203.60 : x
  2. Step 2: Convert to fraction form
    419.87/629.39 = 203.60/x
  3. Step 3: Cross multiply
    419.87x = 629.39 × 203.60
  4. Step 4: Simplify right side
    419.87x = 128,139.64
  5. Step 5: Solve for x
    x = 128,139.64/419.87
  6. Step 6: Final answer
    x = 305.19

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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.