Finding the Fourth Proportional to 2,071.80, 3,105.72 and 772.92

Step by Step Solution

1. Step 1: Write the proportion equation
   2,071.80 : 3,105.72 = 772.92 : x
2. Step 2: Convert to fraction form
   2,071.80/3,105.72 = 772.92/x
3. Step 3: Cross multiply
   2,071.80x = 3,105.72 × 772.92
4. Step 4: Simplify right side
   2,071.80x = 2,400,473.10
5. Step 5: Solve for x
   x = 2,400,473.10/2,071.80
6. Step 6: Final answer
   x = 1,158.64