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Finding the Fourth Proportional to 853.10, 1,279.24 and 419.75

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Solution

The fourth proportional to 853.10, 1,279.24 and 419.75 is: 629.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.10 : 1,279.24 = 419.75 : x
  2. Step 2: Convert to fraction form
    853.10/1,279.24 = 419.75/x
  3. Step 3: Cross multiply
    853.10x = 1,279.24 × 419.75
  4. Step 4: Simplify right side
    853.10x = 536,960.99
  5. Step 5: Solve for x
    x = 536,960.99/853.10
  6. Step 6: Final answer
    x = 629.42

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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.