Finding the Fourth Proportional to 21,536.88, 29,720.79 and 12,105.51

Step by Step Solution

1. Step 1: Write the proportion equation
   21,536.88 : 29,720.79 = 12,105.51 : x
2. Step 2: Convert to fraction form
   21,536.88/29,720.79 = 12,105.51/x
3. Step 3: Cross multiply
   21,536.88x = 29,720.79 × 12,105.51
4. Step 4: Simplify right side
   21,536.88x = 359,785,320.55
5. Step 5: Solve for x
   x = 359,785,320.55/21,536.88
6. Step 6: Final answer
   x = 16,705.55