Finding the Fourth Proportional to 21,056.88, 31,574.69 and 7,899.99

Step by Step Solution

1. Step 1: Write the proportion equation
   21,056.88 : 31,574.69 = 7,899.99 : x
2. Step 2: Convert to fraction form
   21,056.88/31,574.69 = 7,899.99/x
3. Step 3: Cross multiply
   21,056.88x = 31,574.69 × 7,899.99
4. Step 4: Simplify right side
   21,056.88x = 249,439,735.25
5. Step 5: Solve for x
   x = 249,439,735.25/21,056.88
6. Step 6: Final answer
   x = 11,846.00