Finding the Fourth Proportional to 12,986.82, 17,921.82 and 7,018.49

Step by Step Solution

1. Step 1: Write the proportion equation
   12,986.82 : 17,921.82 = 7,018.49 : x
2. Step 2: Convert to fraction form
   12,986.82/17,921.82 = 7,018.49/x
3. Step 3: Cross multiply
   12,986.82x = 17,921.82 × 7,018.49
4. Step 4: Simplify right side
   12,986.82x = 125,784,024.84
5. Step 5: Solve for x
   x = 125,784,024.84/12,986.82
6. Step 6: Final answer
   x = 9,685.51