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Finding the Fourth Proportional to 851.10, 1,278.09 and 419.10

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Solution

The fourth proportional to 851.10, 1,278.09 and 419.10 is: 629.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    851.10 : 1,278.09 = 419.10 : x
  2. Step 2: Convert to fraction form
    851.10/1,278.09 = 419.10/x
  3. Step 3: Cross multiply
    851.10x = 1,278.09 × 419.10
  4. Step 4: Simplify right side
    851.10x = 535,647.52
  5. Step 5: Solve for x
    x = 535,647.52/851.10
  6. Step 6: Final answer
    x = 629.36

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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.