Finding the Fourth Proportional to 3,968.64, 5,445.12 and 3,870.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,968.64 : 5,445.12 = 3,870.72 : x
2. Step 2: Convert to fraction form
   3,968.64/5,445.12 = 3,870.72/x
3. Step 3: Cross multiply
   3,968.64x = 5,445.12 × 3,870.72
4. Step 4: Simplify right side
   3,968.64x = 21,076,534.89
5. Step 5: Solve for x
   x = 21,076,534.89/3,968.64
6. Step 6: Final answer
   x = 5,310.77