Finding the Fourth Proportional to 9,921.54, 13,692.98 and 5,728.98

Step by Step Solution

1. Step 1: Write the proportion equation
   9,921.54 : 13,692.98 = 5,728.98 : x
2. Step 2: Convert to fraction form
   9,921.54/13,692.98 = 5,728.98/x
3. Step 3: Cross multiply
   9,921.54x = 13,692.98 × 5,728.98
4. Step 4: Simplify right side
   9,921.54x = 78,446,808.56
5. Step 5: Solve for x
   x = 78,446,808.56/9,921.54
6. Step 6: Final answer
   x = 7,906.72