Finding the Fourth Proportional to 2,074.15, 3,111.30 and 613.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,074.15 : 3,111.30 = 613.30 : x
2. Step 2: Convert to fraction form
   2,074.15/3,111.30 = 613.30/x
3. Step 3: Cross multiply
   2,074.15x = 3,111.30 × 613.30
4. Step 4: Simplify right side
   2,074.15x = 1,908,160.29
5. Step 5: Solve for x
   x = 1,908,160.29/2,074.15
6. Step 6: Final answer
   x = 919.97