Finding the Fourth Proportional to 2,015.55, 3,022.56 and 782.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,015.55 : 3,022.56 = 782.80 : x
2. Step 2: Convert to fraction form
   2,015.55/3,022.56 = 782.80/x
3. Step 3: Cross multiply
   2,015.55x = 3,022.56 × 782.80
4. Step 4: Simplify right side
   2,015.55x = 2,366,063.28
5. Step 5: Solve for x
   x = 2,366,063.28/2,015.55
6. Step 6: Final answer
   x = 1,173.90