Finding the Fourth Proportional to 10,087.80, 13,920.42 and 5,611.44

Step by Step Solution

1. Step 1: Write the proportion equation
   10,087.80 : 13,920.42 = 5,611.44 : x
2. Step 2: Convert to fraction form
   10,087.80/13,920.42 = 5,611.44/x
3. Step 3: Cross multiply
   10,087.80x = 13,920.42 × 5,611.44
4. Step 4: Simplify right side
   10,087.80x = 78,113,601.60
5. Step 5: Solve for x
   x = 78,113,601.60/10,087.80
6. Step 6: Final answer
   x = 7,743.37