Finding the Fourth Proportional to 28,071.30, 42,106.59 and 8,081.31

Step by Step Solution

1. Step 1: Write the proportion equation
   28,071.30 : 42,106.59 = 8,081.31 : x
2. Step 2: Convert to fraction form
   28,071.30/42,106.59 = 8,081.31/x
3. Step 3: Cross multiply
   28,071.30x = 42,106.59 × 8,081.31
4. Step 4: Simplify right side
   28,071.30x = 340,276,406.83
5. Step 5: Solve for x
   x = 340,276,406.83/28,071.30
6. Step 6: Final answer
   x = 12,121.86