Finding the Fourth Proportional to 3,891.89, 5,370.69 and 2,123.49

Step by Step Solution

1. Step 1: Write the proportion equation
   3,891.89 : 5,370.69 = 2,123.49 : x
2. Step 2: Convert to fraction form
   3,891.89/5,370.69 = 2,123.49/x
3. Step 3: Cross multiply
   3,891.89x = 5,370.69 × 2,123.49
4. Step 4: Simplify right side
   3,891.89x = 11,404,606.51
5. Step 5: Solve for x
   x = 11,404,606.51/3,891.89
6. Step 6: Final answer
   x = 2,930.35