Finding the Fourth Proportional to 2,112.96, 3,167.64 and 815.34

Step by Step Solution

1. Step 1: Write the proportion equation
   2,112.96 : 3,167.64 = 815.34 : x
2. Step 2: Convert to fraction form
   2,112.96/3,167.64 = 815.34/x
3. Step 3: Cross multiply
   2,112.96x = 3,167.64 × 815.34
4. Step 4: Simplify right side
   2,112.96x = 2,582,703.60
5. Step 5: Solve for x
   x = 2,582,703.60/2,112.96
6. Step 6: Final answer
   x = 1,222.32