Finding the Fourth Proportional to 13,196.56, 18,213.60 and 7,891.96

Step by Step Solution

1. Step 1: Write the proportion equation
   13,196.56 : 18,213.60 = 7,891.96 : x
2. Step 2: Convert to fraction form
   13,196.56/18,213.60 = 7,891.96/x
3. Step 3: Cross multiply
   13,196.56x = 18,213.60 × 7,891.96
4. Step 4: Simplify right side
   13,196.56x = 143,741,002.66
5. Step 5: Solve for x
   x = 143,741,002.66/13,196.56
6. Step 6: Final answer
   x = 10,892.31