Finding the Fourth Proportional to 2,099.93, 3,150.16 and 638.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,099.93 : 3,150.16 = 638.89 : x
2. Step 2: Convert to fraction form
   2,099.93/3,150.16 = 638.89/x
3. Step 3: Cross multiply
   2,099.93x = 3,150.16 × 638.89
4. Step 4: Simplify right side
   2,099.93x = 2,012,596.25
5. Step 5: Solve for x
   x = 2,012,596.25/2,099.93
6. Step 6: Final answer
   x = 958.41