Finding the Fourth Proportional to 2,111.59, 3,167.14 and 812.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.59 : 3,167.14 = 812.15 : x
2. Step 2: Convert to fraction form
   2,111.59/3,167.14 = 812.15/x
3. Step 3: Cross multiply
   2,111.59x = 3,167.14 × 812.15
4. Step 4: Simplify right side
   2,111.59x = 2,572,192.75
5. Step 5: Solve for x
   x = 2,572,192.75/2,111.59
6. Step 6: Final answer
   x = 1,218.13