Finding the Fourth Proportional to 21,367.79, 29,495.42 and 12,870.27

Step by Step Solution

1. Step 1: Write the proportion equation
   21,367.79 : 29,495.42 = 12,870.27 : x
2. Step 2: Convert to fraction form
   21,367.79/29,495.42 = 12,870.27/x
3. Step 3: Cross multiply
   21,367.79x = 29,495.42 × 12,870.27
4. Step 4: Simplify right side
   21,367.79x = 379,613,954.81
5. Step 5: Solve for x
   x = 379,613,954.81/21,367.79
6. Step 6: Final answer
   x = 17,765.71