Finding the Fourth Proportional to 21,061.44, 31,591.15 and 5,266.57

Step by Step Solution

1. Step 1: Write the proportion equation
   21,061.44 : 31,591.15 = 5,266.57 : x
2. Step 2: Convert to fraction form
   21,061.44/31,591.15 = 5,266.57/x
3. Step 3: Cross multiply
   21,061.44x = 31,591.15 × 5,266.57
4. Step 4: Simplify right side
   21,061.44x = 166,377,002.86
5. Step 5: Solve for x
   x = 166,377,002.86/21,061.44
6. Step 6: Final answer
   x = 7,899.60