Finding the Fourth Proportional to 3,923.83, 5,415.02 and 2,155.50

Step by Step Solution

1. Step 1: Write the proportion equation
   3,923.83 : 5,415.02 = 2,155.50 : x
2. Step 2: Convert to fraction form
   3,923.83/5,415.02 = 2,155.50/x
3. Step 3: Cross multiply
   3,923.83x = 5,415.02 × 2,155.50
4. Step 4: Simplify right side
   3,923.83x = 11,672,075.61
5. Step 5: Solve for x
   x = 11,672,075.61/3,923.83
6. Step 6: Final answer
   x = 2,974.66