Finding the Fourth Proportional to 11,940.72, 17,912.98 and 3,618.78

Step by Step Solution

1. Step 1: Write the proportion equation
   11,940.72 : 17,912.98 = 3,618.78 : x
2. Step 2: Convert to fraction form
   11,940.72/17,912.98 = 3,618.78/x
3. Step 3: Cross multiply
   11,940.72x = 17,912.98 × 3,618.78
4. Step 4: Simplify right side
   11,940.72x = 64,823,071.11
5. Step 5: Solve for x
   x = 64,823,071.11/11,940.72
6. Step 6: Final answer
   x = 5,428.74