Finding the Fourth Proportional to 1,678.08, 2,513.46 and 810.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,678.08 : 2,513.46 = 810.57 : x
2. Step 2: Convert to fraction form
   1,678.08/2,513.46 = 810.57/x
3. Step 3: Cross multiply
   1,678.08x = 2,513.46 × 810.57
4. Step 4: Simplify right side
   1,678.08x = 2,037,335.27
5. Step 5: Solve for x
   x = 2,037,335.27/1,678.08
6. Step 6: Final answer
   x = 1,214.09