Finding the Fourth Proportional to 21,159.72, 31,742.82 and 5,578.56

Step by Step Solution

1. Step 1: Write the proportion equation
   21,159.72 : 31,742.82 = 5,578.56 : x
2. Step 2: Convert to fraction form
   21,159.72/31,742.82 = 5,578.56/x
3. Step 3: Cross multiply
   21,159.72x = 31,742.82 × 5,578.56
4. Step 4: Simplify right side
   21,159.72x = 177,079,225.94
5. Step 5: Solve for x
   x = 177,079,225.94/21,159.72
6. Step 6: Final answer
   x = 8,368.69