Finding the Fourth Proportional to 3,870.54, 5,378.40 and 3,830.40

Step by Step Solution

1. Step 1: Write the proportion equation
   3,870.54 : 5,378.40 = 3,830.40 : x
2. Step 2: Convert to fraction form
   3,870.54/5,378.40 = 3,830.40/x
3. Step 3: Cross multiply
   3,870.54x = 5,378.40 × 3,830.40
4. Step 4: Simplify right side
   3,870.54x = 20,601,423.36
5. Step 5: Solve for x
   x = 20,601,423.36/3,870.54
6. Step 6: Final answer
   x = 5,322.62