Finding the Fourth Proportional to 2,646.42, 3,960.78 and 2,611.45

Step by Step Solution

1. Step 1: Write the proportion equation
   2,646.42 : 3,960.78 = 2,611.45 : x
2. Step 2: Convert to fraction form
   2,646.42/3,960.78 = 2,611.45/x
3. Step 3: Cross multiply
   2,646.42x = 3,960.78 × 2,611.45
4. Step 4: Simplify right side
   2,646.42x = 10,343,378.93
5. Step 5: Solve for x
   x = 10,343,378.93/2,646.42
6. Step 6: Final answer
   x = 3,908.44