Finding the Fourth Proportional to 2,111.11, 2,913.56 and 1,215.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.11 : 2,913.56 = 1,215.12 : x
2. Step 2: Convert to fraction form
   2,111.11/2,913.56 = 1,215.12/x
3. Step 3: Cross multiply
   2,111.11x = 2,913.56 × 1,215.12
4. Step 4: Simplify right side
   2,111.11x = 3,540,329.88
5. Step 5: Solve for x
   x = 3,540,329.88/2,111.11
6. Step 6: Final answer
   x = 1,677.00