Finding the Fourth Proportional to 13,986.16, 20,969.52 and 5,218.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,986.16 : 20,969.52 = 5,218.72 : x
2. Step 2: Convert to fraction form
   13,986.16/20,969.52 = 5,218.72/x
3. Step 3: Cross multiply
   13,986.16x = 20,969.52 × 5,218.72
4. Step 4: Simplify right side
   13,986.16x = 109,434,053.41
5. Step 5: Solve for x
   x = 109,434,053.41/13,986.16
6. Step 6: Final answer
   x = 7,824.45