Finding the Fourth Proportional to 2,091.32, 3,136.18 and 685.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,091.32 : 3,136.18 = 685.40 : x
2. Step 2: Convert to fraction form
   2,091.32/3,136.18 = 685.40/x
3. Step 3: Cross multiply
   2,091.32x = 3,136.18 × 685.40
4. Step 4: Simplify right side
   2,091.32x = 2,149,543.90
5. Step 5: Solve for x
   x = 2,149,543.90/2,091.32
6. Step 6: Final answer
   x = 1,027.84