Finding the Fourth Proportional to 2,100.21, 3,150.22 and 783.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,100.21 : 3,150.22 = 783.87 : x
2. Step 2: Convert to fraction form
   2,100.21/3,150.22 = 783.87/x
3. Step 3: Cross multiply
   2,100.21x = 3,150.22 × 783.87
4. Step 4: Simplify right side
   2,100.21x = 2,469,347.71
5. Step 5: Solve for x
   x = 2,469,347.71/2,100.21
6. Step 6: Final answer
   x = 1,175.76