Home / 1,286.25-1,928.81-408.59

Finding the Fourth Proportional to 1,286.25, 1,928.81 and 408.59

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Solution

The fourth proportional to 1,286.25, 1,928.81 and 408.59 is: 612.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.25 : 1,928.81 = 408.59 : x
  2. Step 2: Convert to fraction form
    1,286.25/1,928.81 = 408.59/x
  3. Step 3: Cross multiply
    1,286.25x = 1,928.81 × 408.59
  4. Step 4: Simplify right side
    1,286.25x = 788,101.94
  5. Step 5: Solve for x
    x = 788,101.94/1,286.25
  6. Step 6: Final answer
    x = 612.71

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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.