Finding the Fourth Proportional to 3,886.84, 5,367.78 and 2,561.56

Step by Step Solution

1. Step 1: Write the proportion equation
   3,886.84 : 5,367.78 = 2,561.56 : x
2. Step 2: Convert to fraction form
   3,886.84/5,367.78 = 2,561.56/x
3. Step 3: Cross multiply
   3,886.84x = 5,367.78 × 2,561.56
4. Step 4: Simplify right side
   3,886.84x = 13,749,890.54
5. Step 5: Solve for x
   x = 13,749,890.54/3,886.84
6. Step 6: Final answer
   x = 3,537.55