Finding the Fourth Proportional to 2,638.72, 3,957.56 and 764.83

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638.72 : 3,957.56 = 764.83 : x
2. Step 2: Convert to fraction form
   2,638.72/3,957.56 = 764.83/x
3. Step 3: Cross multiply
   2,638.72x = 3,957.56 × 764.83
4. Step 4: Simplify right side
   2,638.72x = 3,026,864.61
5. Step 5: Solve for x
   x = 3,026,864.61/2,638.72
6. Step 6: Final answer
   x = 1,147.10