Finding the Fourth Proportional to 2,663.78, 3,680.53 and 1,916.26

Step by Step Solution

1. Step 1: Write the proportion equation
   2,663.78 : 3,680.53 = 1,916.26 : x
2. Step 2: Convert to fraction form
   2,663.78/3,680.53 = 1,916.26/x
3. Step 3: Cross multiply
   2,663.78x = 3,680.53 × 1,916.26
4. Step 4: Simplify right side
   2,663.78x = 7,052,852.42
5. Step 5: Solve for x
   x = 7,052,852.42/2,663.78
6. Step 6: Final answer
   x = 2,647.69