Finding the Fourth Proportional to 2,099.84, 3,150.10 and 638.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,099.84 : 3,150.10 = 638.88 : x
2. Step 2: Convert to fraction form
   2,099.84/3,150.10 = 638.88/x
3. Step 3: Cross multiply
   2,099.84x = 3,150.10 × 638.88
4. Step 4: Simplify right side
   2,099.84x = 2,012,535.89
5. Step 5: Solve for x
   x = 2,012,535.89/2,099.84
6. Step 6: Final answer
   x = 958.42