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Finding the Fourth Proportional to 419.14, 578.39 and 279.51

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Solution

The fourth proportional to 419.14, 578.39 and 279.51 is: 385.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.14 : 578.39 = 279.51 : x
  2. Step 2: Convert to fraction form
    419.14/578.39 = 279.51/x
  3. Step 3: Cross multiply
    419.14x = 578.39 × 279.51
  4. Step 4: Simplify right side
    419.14x = 161,662.90
  5. Step 5: Solve for x
    x = 161,662.90/419.14
  6. Step 6: Final answer
    x = 385.71

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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.