Finding the Fourth Proportional to 21,153.02, 31,707.20 and 7,099.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,153.02 : 31,707.20 = 7,099.72 : x
2. Step 2: Convert to fraction form
   21,153.02/31,707.20 = 7,099.72/x
3. Step 3: Cross multiply
   21,153.02x = 31,707.20 × 7,099.72
4. Step 4: Simplify right side
   21,153.02x = 225,112,241.98
5. Step 5: Solve for x
   x = 225,112,241.98/21,153.02
6. Step 6: Final answer
   x = 10,642.09