Finding the Fourth Proportional to 1,945.16, 2,916.98 and 678.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,945.16 : 2,916.98 = 678.39 : x
2. Step 2: Convert to fraction form
   1,945.16/2,916.98 = 678.39/x
3. Step 3: Cross multiply
   1,945.16x = 2,916.98 × 678.39
4. Step 4: Simplify right side
   1,945.16x = 1,978,838.28
5. Step 5: Solve for x
   x = 1,978,838.28/1,945.16
6. Step 6: Final answer
   x = 1,017.31