Finding the Fourth Proportional to 21,111.12, 29,136.96 and 12,157.02

Step by Step Solution

1. Step 1: Write the proportion equation
   21,111.12 : 29,136.96 = 12,157.02 : x
2. Step 2: Convert to fraction form
   21,111.12/29,136.96 = 12,157.02/x
3. Step 3: Cross multiply
   21,111.12x = 29,136.96 × 12,157.02
4. Step 4: Simplify right side
   21,111.12x = 354,218,605.46
5. Step 5: Solve for x
   x = 354,218,605.46/21,111.12
6. Step 6: Final answer
   x = 16,778.77