Finding the Fourth Proportional to 21,687.90, 32,334.28 and 21,142.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,687.90 : 32,334.28 = 21,142.52 : x
2. Step 2: Convert to fraction form
   21,687.90/32,334.28 = 21,142.52/x
3. Step 3: Cross multiply
   21,687.90x = 32,334.28 × 21,142.52
4. Step 4: Simplify right side
   21,687.90x = 683,628,172.37
5. Step 5: Solve for x
   x = 683,628,172.37/21,687.90
6. Step 6: Final answer
   x = 31,521.18