Finding the Fourth Proportional to 2,621.50, 3,931.41 and 866.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,621.50 : 3,931.41 = 866.10 : x
2. Step 2: Convert to fraction form
   2,621.50/3,931.41 = 866.10/x
3. Step 3: Cross multiply
   2,621.50x = 3,931.41 × 866.10
4. Step 4: Simplify right side
   2,621.50x = 3,404,974.54
5. Step 5: Solve for x
   x = 3,404,974.54/2,621.50
6. Step 6: Final answer
   x = 1,298.86