Finding the Fourth Proportional to 2,111.84, 3,169.20 and 958.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.84 : 3,169.20 = 958.40 : x
2. Step 2: Convert to fraction form
   2,111.84/3,169.20 = 958.40/x
3. Step 3: Cross multiply
   2,111.84x = 3,169.20 × 958.40
4. Step 4: Simplify right side
   2,111.84x = 3,037,361.28
5. Step 5: Solve for x
   x = 3,037,361.28/2,111.84
6. Step 6: Final answer
   x = 1,438.25