Finding the Fourth Proportional to 28,516.82, 42,786.18 and 20,091.42

Step by Step Solution

1. Step 1: Write the proportion equation
   28,516.82 : 42,786.18 = 20,091.42 : x
2. Step 2: Convert to fraction form
   28,516.82/42,786.18 = 20,091.42/x
3. Step 3: Cross multiply
   28,516.82x = 42,786.18 × 20,091.42
4. Step 4: Simplify right side
   28,516.82x = 859,635,112.58
5. Step 5: Solve for x
   x = 859,635,112.58/28,516.82
6. Step 6: Final answer
   x = 30,144.84