Finding the Fourth Proportional to 2,109.18, 3,163.94 and 648.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.18 : 3,163.94 = 648.15 : x
2. Step 2: Convert to fraction form
   2,109.18/3,163.94 = 648.15/x
3. Step 3: Cross multiply
   2,109.18x = 3,163.94 × 648.15
4. Step 4: Simplify right side
   2,109.18x = 2,050,704.47
5. Step 5: Solve for x
   x = 2,050,704.47/2,109.18
6. Step 6: Final answer
   x = 972.28