Finding the Fourth Proportional to 28,105.74, 42,158.60 and 8,398.13

Step by Step Solution

1. Step 1: Write the proportion equation
   28,105.74 : 42,158.60 = 8,398.13 : x
2. Step 2: Convert to fraction form
   28,105.74/42,158.60 = 8,398.13/x
3. Step 3: Cross multiply
   28,105.74x = 42,158.60 × 8,398.13
4. Step 4: Simplify right side
   28,105.74x = 354,053,150.63
5. Step 5: Solve for x
   x = 354,053,150.63/28,105.74
6. Step 6: Final answer
   x = 12,597.18