Finding the Fourth Proportional to 2,810.78, 4,215.43 and 835.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,810.78 : 4,215.43 = 835.87 : x
2. Step 2: Convert to fraction form
   2,810.78/4,215.43 = 835.87/x
3. Step 3: Cross multiply
   2,810.78x = 4,215.43 × 835.87
4. Step 4: Simplify right side
   2,810.78x = 3,523,561.17
5. Step 5: Solve for x
   x = 3,523,561.17/2,810.78
6. Step 6: Final answer
   x = 1,253.59