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Finding the Fourth Proportional to 419.24, 578.30 and 309

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Solution

The fourth proportional to 419.24, 578.30 and 309 is: 426.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.24 : 578.30 = 309 : x
  2. Step 2: Convert to fraction form
    419.24/578.30 = 309/x
  3. Step 3: Cross multiply
    419.24x = 578.30 × 309
  4. Step 4: Simplify right side
    419.24x = 178,694.70
  5. Step 5: Solve for x
    x = 178,694.70/419.24
  6. Step 6: Final answer
    x = 426.23

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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.