Finding the Fourth Proportional to 2,123.96, 3,186.07 and 890.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.96 : 3,186.07 = 890.12 : x
2. Step 2: Convert to fraction form
   2,123.96/3,186.07 = 890.12/x
3. Step 3: Cross multiply
   2,123.96x = 3,186.07 × 890.12
4. Step 4: Simplify right side
   2,123.96x = 2,835,990.37
5. Step 5: Solve for x
   x = 2,835,990.37/2,123.96
6. Step 6: Final answer
   x = 1,335.24