Finding the Fourth Proportional to 9,954.71, 13,737.78 and 5,478.57

Step by Step Solution

1. Step 1: Write the proportion equation
   9,954.71 : 13,737.78 = 5,478.57 : x
2. Step 2: Convert to fraction form
   9,954.71/13,737.78 = 5,478.57/x
3. Step 3: Cross multiply
   9,954.71x = 13,737.78 × 5,478.57
4. Step 4: Simplify right side
   9,954.71x = 75,263,389.37
5. Step 5: Solve for x
   x = 75,263,389.37/9,954.71
6. Step 6: Final answer
   x = 7,560.58