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Finding the Fourth Proportional to 419.89, 629.28 and 309.69

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Solution

The fourth proportional to 419.89, 629.28 and 309.69 is: 464.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.89 : 629.28 = 309.69 : x
  2. Step 2: Convert to fraction form
    419.89/629.28 = 309.69/x
  3. Step 3: Cross multiply
    419.89x = 629.28 × 309.69
  4. Step 4: Simplify right side
    419.89x = 194,881.72
  5. Step 5: Solve for x
    x = 194,881.72/419.89
  6. Step 6: Final answer
    x = 464.13

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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.