Home / 1,286.57-1,929.83-409.15

Finding the Fourth Proportional to 1,286.57, 1,929.83 and 409.15

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Solution

The fourth proportional to 1,286.57, 1,929.83 and 409.15 is: 613.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.57 : 1,929.83 = 409.15 : x
  2. Step 2: Convert to fraction form
    1,286.57/1,929.83 = 409.15/x
  3. Step 3: Cross multiply
    1,286.57x = 1,929.83 × 409.15
  4. Step 4: Simplify right side
    1,286.57x = 789,589.94
  5. Step 5: Solve for x
    x = 789,589.94/1,286.57
  6. Step 6: Final answer
    x = 613.72

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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.