Finding the Fourth Proportional to 2,167.79, 2,991.32 and 1,223.48

Step by Step Solution

1. Step 1: Write the proportion equation
   2,167.79 : 2,991.32 = 1,223.48 : x
2. Step 2: Convert to fraction form
   2,167.79/2,991.32 = 1,223.48/x
3. Step 3: Cross multiply
   2,167.79x = 2,991.32 × 1,223.48
4. Step 4: Simplify right side
   2,167.79x = 3,659,821.55
5. Step 5: Solve for x
   x = 3,659,821.55/2,167.79
6. Step 6: Final answer
   x = 1,688.28