Finding the Fourth Proportional to 2,216.12, 3,326.61 and 918.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,216.12 : 3,326.61 = 918.50 : x
2. Step 2: Convert to fraction form
   2,216.12/3,326.61 = 918.50/x
3. Step 3: Cross multiply
   2,216.12x = 3,326.61 × 918.50
4. Step 4: Simplify right side
   2,216.12x = 3,055,485.98
5. Step 5: Solve for x
   x = 3,055,485.98/2,216.12
6. Step 6: Final answer
   x = 1,378.76