Finding the Fourth Proportional to 21,991.41, 32,978.88 and 8,839.31

Step by Step Solution

1. Step 1: Write the proportion equation
   21,991.41 : 32,978.88 = 8,839.31 : x
2. Step 2: Convert to fraction form
   21,991.41/32,978.88 = 8,839.31/x
3. Step 3: Cross multiply
   21,991.41x = 32,978.88 × 8,839.31
4. Step 4: Simplify right side
   21,991.41x = 291,510,378.88
5. Step 5: Solve for x
   x = 291,510,378.88/21,991.41
6. Step 6: Final answer
   x = 13,255.65