Finding the Fourth Proportional to 2,607.72, 3,911.71 and 659.94

Step by Step Solution

1. Step 1: Write the proportion equation
   2,607.72 : 3,911.71 = 659.94 : x
2. Step 2: Convert to fraction form
   2,607.72/3,911.71 = 659.94/x
3. Step 3: Cross multiply
   2,607.72x = 3,911.71 × 659.94
4. Step 4: Simplify right side
   2,607.72x = 2,581,493.90
5. Step 5: Solve for x
   x = 2,581,493.90/2,607.72
6. Step 6: Final answer
   x = 989.94