Finding the Fourth Proportional to 3,918.79, 5,407.89 and 2,150.42

Step by Step Solution

1. Step 1: Write the proportion equation
   3,918.79 : 5,407.89 = 2,150.42 : x
2. Step 2: Convert to fraction form
   3,918.79/5,407.89 = 2,150.42/x
3. Step 3: Cross multiply
   3,918.79x = 5,407.89 × 2,150.42
4. Step 4: Simplify right side
   3,918.79x = 11,629,234.81
5. Step 5: Solve for x
   x = 11,629,234.81/3,918.79
6. Step 6: Final answer
   x = 2,967.56