Finding the Fourth Proportional to 28,112.17, 42,175.56 and 8,390.73

Step by Step Solution

1. Step 1: Write the proportion equation
   28,112.17 : 42,175.56 = 8,390.73 : x
2. Step 2: Convert to fraction form
   28,112.17/42,175.56 = 8,390.73/x
3. Step 3: Cross multiply
   28,112.17x = 42,175.56 × 8,390.73
4. Step 4: Simplify right side
   28,112.17x = 353,883,736.56
5. Step 5: Solve for x
   x = 353,883,736.56/28,112.17
6. Step 6: Final answer
   x = 12,588.28