Finding the Fourth Proportional to 2,931.72, 4,043.30 and 2,640.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,931.72 : 4,043.30 = 2,640.12 : x
2. Step 2: Convert to fraction form
   2,931.72/4,043.30 = 2,640.12/x
3. Step 3: Cross multiply
   2,931.72x = 4,043.30 × 2,640.12
4. Step 4: Simplify right side
   2,931.72x = 10,674,784.00
5. Step 5: Solve for x
   x = 10,674,784.00/2,931.72
6. Step 6: Final answer
   x = 3,641.13