Finding the Fourth Proportional to 2,100.93, 3,150.37 and 639.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,100.93 : 3,150.37 = 639.69 : x
2. Step 2: Convert to fraction form
   2,100.93/3,150.37 = 639.69/x
3. Step 3: Cross multiply
   2,100.93x = 3,150.37 × 639.69
4. Step 4: Simplify right side
   2,100.93x = 2,015,260.19
5. Step 5: Solve for x
   x = 2,015,260.19/2,100.93
6. Step 6: Final answer
   x = 959.22