Finding the Fourth Proportional to 2,111.31, 2,913.69 and 1,167.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.31 : 2,913.69 = 1,167.15 : x
2. Step 2: Convert to fraction form
   2,111.31/2,913.69 = 1,167.15/x
3. Step 3: Cross multiply
   2,111.31x = 2,913.69 × 1,167.15
4. Step 4: Simplify right side
   2,111.31x = 3,400,713.28
5. Step 5: Solve for x
   x = 3,400,713.28/2,111.31
6. Step 6: Final answer
   x = 1,610.71