Finding the Fourth Proportional to 6,328.72, 8,731.32 and 3,970

Step by Step Solution

1. Step 1: Write the proportion equation
   6,328.72 : 8,731.32 = 3,970 : x
2. Step 2: Convert to fraction form
   6,328.72/8,731.32 = 3,970/x
3. Step 3: Cross multiply
   6,328.72x = 8,731.32 × 3,970
4. Step 4: Simplify right side
   6,328.72x = 34,663,340.40
5. Step 5: Solve for x
   x = 34,663,340.40/6,328.72
6. Step 6: Final answer
   x = 5,477.15