Finding the Fourth Proportional to 3,918.53, 5,407.56 and 2,150.15

Step by Step Solution

1. Step 1: Write the proportion equation
   3,918.53 : 5,407.56 = 2,150.15 : x
2. Step 2: Convert to fraction form
   3,918.53/5,407.56 = 2,150.15/x
3. Step 3: Cross multiply
   3,918.53x = 5,407.56 × 2,150.15
4. Step 4: Simplify right side
   3,918.53x = 11,627,038.10
5. Step 5: Solve for x
   x = 11,627,038.10/3,918.53
6. Step 6: Final answer
   x = 2,967.20