Finding the Fourth Proportional to 13,679.33, 20,509.81 and 7,019.87

Step by Step Solution

1. Step 1: Write the proportion equation
   13,679.33 : 20,509.81 = 7,019.87 : x
2. Step 2: Convert to fraction form
   13,679.33/20,509.81 = 7,019.87/x
3. Step 3: Cross multiply
   13,679.33x = 20,509.81 × 7,019.87
4. Step 4: Simplify right side
   13,679.33x = 143,976,079.83
5. Step 5: Solve for x
   x = 143,976,079.83/13,679.33
6. Step 6: Final answer
   x = 10,525.09