Finding the Fourth Proportional to 12,696.21, 17,512.61 and 7,972.29

Step by Step Solution

1. Step 1: Write the proportion equation
   12,696.21 : 17,512.61 = 7,972.29 : x
2. Step 2: Convert to fraction form
   12,696.21/17,512.61 = 7,972.29/x
3. Step 3: Cross multiply
   12,696.21x = 17,512.61 × 7,972.29
4. Step 4: Simplify right side
   12,696.21x = 139,615,565.72
5. Step 5: Solve for x
   x = 139,615,565.72/12,696.21
6. Step 6: Final answer
   x = 10,996.63