Finding the Fourth Proportional to 21,518.25, 29,696.70 and 12,086.82

Step by Step Solution

1. Step 1: Write the proportion equation
   21,518.25 : 29,696.70 = 12,086.82 : x
2. Step 2: Convert to fraction form
   21,518.25/29,696.70 = 12,086.82/x
3. Step 3: Cross multiply
   21,518.25x = 29,696.70 × 12,086.82
4. Step 4: Simplify right side
   21,518.25x = 358,938,667.49
5. Step 5: Solve for x
   x = 358,938,667.49/21,518.25
6. Step 6: Final answer
   x = 16,680.66