Finding the Fourth Proportional to 12,636.72, 18,957.24 and 3,870.72

Step by Step Solution

1. Step 1: Write the proportion equation
   12,636.72 : 18,957.24 = 3,870.72 : x
2. Step 2: Convert to fraction form
   12,636.72/18,957.24 = 3,870.72/x
3. Step 3: Cross multiply
   12,636.72x = 18,957.24 × 3,870.72
4. Step 4: Simplify right side
   12,636.72x = 73,378,168.01
5. Step 5: Solve for x
   x = 73,378,168.01/12,636.72
6. Step 6: Final answer
   x = 5,806.74