Finding the Fourth Proportional to 9,611.50, 13,263.89 and 5,419.90

Step by Step Solution

1. Step 1: Write the proportion equation
   9,611.50 : 13,263.89 = 5,419.90 : x
2. Step 2: Convert to fraction form
   9,611.50/13,263.89 = 5,419.90/x
3. Step 3: Cross multiply
   9,611.50x = 13,263.89 × 5,419.90
4. Step 4: Simplify right side
   9,611.50x = 71,888,957.41
5. Step 5: Solve for x
   x = 71,888,957.41/9,611.50
6. Step 6: Final answer
   x = 7,479.47