Finding the Fourth Proportional to 21,855.99, 32,736.60 and 13,538.10

Step by Step Solution

1. Step 1: Write the proportion equation
   21,855.99 : 32,736.60 = 13,538.10 : x
2. Step 2: Convert to fraction form
   21,855.99/32,736.60 = 13,538.10/x
3. Step 3: Cross multiply
   21,855.99x = 32,736.60 × 13,538.10
4. Step 4: Simplify right side
   21,855.99x = 443,191,364.46
5. Step 5: Solve for x
   x = 443,191,364.46/21,855.99
6. Step 6: Final answer
   x = 20,277.80