Finding the Fourth Proportional to 2,574.56, 3,860.22 and 842.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,574.56 : 3,860.22 = 842.78 : x
2. Step 2: Convert to fraction form
   2,574.56/3,860.22 = 842.78/x
3. Step 3: Cross multiply
   2,574.56x = 3,860.22 × 842.78
4. Step 4: Simplify right side
   2,574.56x = 3,253,316.21
5. Step 5: Solve for x
   x = 3,253,316.21/2,574.56
6. Step 6: Final answer
   x = 1,263.64