Finding the Fourth Proportional to 2,638.16, 3,957.72 and 906.36

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638.16 : 3,957.72 = 906.36 : x
2. Step 2: Convert to fraction form
   2,638.16/3,957.72 = 906.36/x
3. Step 3: Cross multiply
   2,638.16x = 3,957.72 × 906.36
4. Step 4: Simplify right side
   2,638.16x = 3,587,119.10
5. Step 5: Solve for x
   x = 3,587,119.10/2,638.16
6. Step 6: Final answer
   x = 1,359.70