Finding the Fourth Proportional to 2,172.15, 3,258.29 and 939.59

Step by Step Solution

1. Step 1: Write the proportion equation
   2,172.15 : 3,258.29 = 939.59 : x
2. Step 2: Convert to fraction form
   2,172.15/3,258.29 = 939.59/x
3. Step 3: Cross multiply
   2,172.15x = 3,258.29 × 939.59
4. Step 4: Simplify right side
   2,172.15x = 3,061,454.98
5. Step 5: Solve for x
   x = 3,061,454.98/2,172.15
6. Step 6: Final answer
   x = 1,409.41