Finding the Fourth Proportional to 2,634.48, 3,949.92 and 990.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,634.48 : 3,949.92 = 990.72 : x
2. Step 2: Convert to fraction form
   2,634.48/3,949.92 = 990.72/x
3. Step 3: Cross multiply
   2,634.48x = 3,949.92 × 990.72
4. Step 4: Simplify right side
   2,634.48x = 3,913,264.74
5. Step 5: Solve for x
   x = 3,913,264.74/2,634.48
6. Step 6: Final answer
   x = 1,485.40