Finding the Fourth Proportional to 2,631.72, 3,944.34 and 2,145.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,631.72 : 3,944.34 = 2,145.72 : x
2. Step 2: Convert to fraction form
   2,631.72/3,944.34 = 2,145.72/x
3. Step 3: Cross multiply
   2,631.72x = 3,944.34 × 2,145.72
4. Step 4: Simplify right side
   2,631.72x = 8,463,449.22
5. Step 5: Solve for x
   x = 8,463,449.22/2,631.72
6. Step 6: Final answer
   x = 3,215.94