Finding the Fourth Proportional to 12,878.67, 19,319.31 and 3,993.69

Step by Step Solution

1. Step 1: Write the proportion equation
   12,878.67 : 19,319.31 = 3,993.69 : x
2. Step 2: Convert to fraction form
   12,878.67/19,319.31 = 3,993.69/x
3. Step 3: Cross multiply
   12,878.67x = 19,319.31 × 3,993.69
4. Step 4: Simplify right side
   12,878.67x = 77,155,335.15
5. Step 5: Solve for x
   x = 77,155,335.15/12,878.67
6. Step 6: Final answer
   x = 5,990.94