Finding the Fourth Proportional to 12,516.40, 17,270.96 and 7,139.56

Step by Step Solution

1. Step 1: Write the proportion equation
   12,516.40 : 17,270.96 = 7,139.56 : x
2. Step 2: Convert to fraction form
   12,516.40/17,270.96 = 7,139.56/x
3. Step 3: Cross multiply
   12,516.40x = 17,270.96 × 7,139.56
4. Step 4: Simplify right side
   12,516.40x = 123,307,055.18
5. Step 5: Solve for x
   x = 123,307,055.18/12,516.40
6. Step 6: Final answer
   x = 9,851.64