Finding the Fourth Proportional to 2,137.50, 3,200.78 and 1,211.68

Step by Step Solution

1. Step 1: Write the proportion equation
   2,137.50 : 3,200.78 = 1,211.68 : x
2. Step 2: Convert to fraction form
   2,137.50/3,200.78 = 1,211.68/x
3. Step 3: Cross multiply
   2,137.50x = 3,200.78 × 1,211.68
4. Step 4: Simplify right side
   2,137.50x = 3,878,321.11
5. Step 5: Solve for x
   x = 3,878,321.11/2,137.50
6. Step 6: Final answer
   x = 1,814.42