Finding the Fourth Proportional to 2,745.28, 4,117.56 and 990.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,745.28 : 4,117.56 = 990.10 : x
2. Step 2: Convert to fraction form
   2,745.28/4,117.56 = 990.10/x
3. Step 3: Cross multiply
   2,745.28x = 4,117.56 × 990.10
4. Step 4: Simplify right side
   2,745.28x = 4,076,796.16
5. Step 5: Solve for x
   x = 4,076,796.16/2,745.28
6. Step 6: Final answer
   x = 1,485.02