Finding the Fourth Proportional to 13,479.82, 20,188.56 and 13,012.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,479.82 : 20,188.56 = 13,012.72 : x
2. Step 2: Convert to fraction form
   13,479.82/20,188.56 = 13,012.72/x
3. Step 3: Cross multiply
   13,479.82x = 20,188.56 × 13,012.72
4. Step 4: Simplify right side
   13,479.82x = 262,708,078.48
5. Step 5: Solve for x
   x = 262,708,078.48/13,479.82
6. Step 6: Final answer
   x = 19,488.99