Finding the Fourth Proportional to 15,912.42, 21,965.05 and 13,665.27

Step by Step Solution

1. Step 1: Write the proportion equation
   15,912.42 : 21,965.05 = 13,665.27 : x
2. Step 2: Convert to fraction form
   15,912.42/21,965.05 = 13,665.27/x
3. Step 3: Cross multiply
   15,912.42x = 21,965.05 × 13,665.27
4. Step 4: Simplify right side
   15,912.42x = 300,158,338.81
5. Step 5: Solve for x
   x = 300,158,338.81/15,912.42
6. Step 6: Final answer
   x = 18,863.15