Finding the Fourth Proportional to 2,657.72, 3,987.12 and 926.48

Step by Step Solution

1. Step 1: Write the proportion equation
   2,657.72 : 3,987.12 = 926.48 : x
2. Step 2: Convert to fraction form
   2,657.72/3,987.12 = 926.48/x
3. Step 3: Cross multiply
   2,657.72x = 3,987.12 × 926.48
4. Step 4: Simplify right side
   2,657.72x = 3,693,986.94
5. Step 5: Solve for x
   x = 3,693,986.94/2,657.72
6. Step 6: Final answer
   x = 1,389.91