Finding the Fourth Proportional to 2,111.40, 3,165.39 and 879.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.40 : 3,165.39 = 879.74 : x
2. Step 2: Convert to fraction form
   2,111.40/3,165.39 = 879.74/x
3. Step 3: Cross multiply
   2,111.40x = 3,165.39 × 879.74
4. Step 4: Simplify right side
   2,111.40x = 2,784,720.20
5. Step 5: Solve for x
   x = 2,784,720.20/2,111.40
6. Step 6: Final answer
   x = 1,318.90