Finding the Fourth Proportional to 2,245.89, 3,099.16 and 1,288.81

Step by Step Solution

1. Step 1: Write the proportion equation
   2,245.89 : 3,099.16 = 1,288.81 : x
2. Step 2: Convert to fraction form
   2,245.89/3,099.16 = 1,288.81/x
3. Step 3: Cross multiply
   2,245.89x = 3,099.16 × 1,288.81
4. Step 4: Simplify right side
   2,245.89x = 3,994,233.88
5. Step 5: Solve for x
   x = 3,994,233.88/2,245.89
6. Step 6: Final answer
   x = 1,778.46