Finding the Fourth Proportional to 3,899.89, 5,381.56 and 2,221.24

Step by Step Solution

1. Step 1: Write the proportion equation
   3,899.89 : 5,381.56 = 2,221.24 : x
2. Step 2: Convert to fraction form
   3,899.89/5,381.56 = 2,221.24/x
3. Step 3: Cross multiply
   3,899.89x = 5,381.56 × 2,221.24
4. Step 4: Simplify right side
   3,899.89x = 11,953,736.33
5. Step 5: Solve for x
   x = 11,953,736.33/3,899.89
6. Step 6: Final answer
   x = 3,065.15