Finding the Fourth Proportional to 12,945.68, 17,862.72 and 7,278.80

Step by Step Solution

1. Step 1: Write the proportion equation
   12,945.68 : 17,862.72 = 7,278.80 : x
2. Step 2: Convert to fraction form
   12,945.68/17,862.72 = 7,278.80/x
3. Step 3: Cross multiply
   12,945.68x = 17,862.72 × 7,278.80
4. Step 4: Simplify right side
   12,945.68x = 130,019,166.34
5. Step 5: Solve for x
   x = 130,019,166.34/12,945.68
6. Step 6: Final answer
   x = 10,043.44