Finding the Fourth Proportional to 1,391.96, 1,919.08 and 1,156.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,391.96 : 1,919.08 = 1,156.12 : x
2. Step 2: Convert to fraction form
   1,391.96/1,919.08 = 1,156.12/x
3. Step 3: Cross multiply
   1,391.96x = 1,919.08 × 1,156.12
4. Step 4: Simplify right side
   1,391.96x = 2,218,686.77
5. Step 5: Solve for x
   x = 2,218,686.77/1,391.96
6. Step 6: Final answer
   x = 1,593.93