Finding the Fourth Proportional to 21,091.77, 31,686.69 and 19,958.01

Step by Step Solution

1. Step 1: Write the proportion equation
   21,091.77 : 31,686.69 = 19,958.01 : x
2. Step 2: Convert to fraction form
   21,091.77/31,686.69 = 19,958.01/x
3. Step 3: Cross multiply
   21,091.77x = 31,686.69 × 19,958.01
4. Step 4: Simplify right side
   21,091.77x = 632,403,275.89
5. Step 5: Solve for x
   x = 632,403,275.89/21,091.77
6. Step 6: Final answer
   x = 29,983.41