Finding the Fourth Proportional to 2,085.93, 3,128.93 and 990.07

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.93 : 3,128.93 = 990.07 : x
2. Step 2: Convert to fraction form
   2,085.93/3,128.93 = 990.07/x
3. Step 3: Cross multiply
   2,085.93x = 3,128.93 × 990.07
4. Step 4: Simplify right side
   2,085.93x = 3,097,868.27
5. Step 5: Solve for x
   x = 3,097,868.27/2,085.93
6. Step 6: Final answer
   x = 1,485.13