Finding the Fourth Proportional to 21,155.77, 31,736.38 and 7,109.74

Step by Step Solution

1. Step 1: Write the proportion equation
   21,155.77 : 31,736.38 = 7,109.74 : x
2. Step 2: Convert to fraction form
   21,155.77/31,736.38 = 7,109.74/x
3. Step 3: Cross multiply
   21,155.77x = 31,736.38 × 7,109.74
4. Step 4: Simplify right side
   21,155.77x = 225,637,410.34
5. Step 5: Solve for x
   x = 225,637,410.34/21,155.77
6. Step 6: Final answer
   x = 10,665.53