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Finding the Fourth Proportional to 419.20, 578.12 and 279.32

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Solution

The fourth proportional to 419.20, 578.12 and 279.32 is: 385.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.20 : 578.12 = 279.32 : x
  2. Step 2: Convert to fraction form
    419.20/578.12 = 279.32/x
  3. Step 3: Cross multiply
    419.20x = 578.12 × 279.32
  4. Step 4: Simplify right side
    419.20x = 161,480.48
  5. Step 5: Solve for x
    x = 161,480.48/419.20
  6. Step 6: Final answer
    x = 385.21

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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.