Finding the Fourth Proportional to 2,810.21, 4,215.78 and 1,055.35

Step by Step Solution

1. Step 1: Write the proportion equation
   2,810.21 : 4,215.78 = 1,055.35 : x
2. Step 2: Convert to fraction form
   2,810.21/4,215.78 = 1,055.35/x
3. Step 3: Cross multiply
   2,810.21x = 4,215.78 × 1,055.35
4. Step 4: Simplify right side
   2,810.21x = 4,449,123.42
5. Step 5: Solve for x
   x = 4,449,123.42/2,810.21
6. Step 6: Final answer
   x = 1,583.20