Finding the Fourth Proportional to 21,131.28, 31,705.83 and 10,611

Step by Step Solution

1. Step 1: Write the proportion equation
   21,131.28 : 31,705.83 = 10,611 : x
2. Step 2: Convert to fraction form
   21,131.28/31,705.83 = 10,611/x
3. Step 3: Cross multiply
   21,131.28x = 31,705.83 × 10,611
4. Step 4: Simplify right side
   21,131.28x = 336,430,562.13
5. Step 5: Solve for x
   x = 336,430,562.13/21,131.28
6. Step 6: Final answer
   x = 15,920.97