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Finding the Fourth Proportional to 419.40, 629.15 and 155.81

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Solution

The fourth proportional to 419.40, 629.15 and 155.81 is: 233.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.40 : 629.15 = 155.81 : x
  2. Step 2: Convert to fraction form
    419.40/629.15 = 155.81/x
  3. Step 3: Cross multiply
    419.40x = 629.15 × 155.81
  4. Step 4: Simplify right side
    419.40x = 98,027.86
  5. Step 5: Solve for x
    x = 98,027.86/419.40
  6. Step 6: Final answer
    x = 233.73

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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.