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Finding the Fourth Proportional to 419.97, 579.24 and 309.21

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Solution

The fourth proportional to 419.97, 579.24 and 309.21 is: 426.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.97 : 579.24 = 309.21 : x
  2. Step 2: Convert to fraction form
    419.97/579.24 = 309.21/x
  3. Step 3: Cross multiply
    419.97x = 579.24 × 309.21
  4. Step 4: Simplify right side
    419.97x = 179,106.80
  5. Step 5: Solve for x
    x = 179,106.80/419.97
  6. Step 6: Final answer
    x = 426.48

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.