Finding the Fourth Proportional to 78,091.70, 117,113.31 and 28,165.31

Step by Step Solution

1. Step 1: Write the proportion equation
   78,091.70 : 117,113.31 = 28,165.31 : x
2. Step 2: Convert to fraction form
   78,091.70/117,113.31 = 28,165.31/x
3. Step 3: Cross multiply
   78,091.70x = 117,113.31 × 28,165.31
4. Step 4: Simplify right side
   78,091.70x = 3,298,532,681.28
5. Step 5: Solve for x
   x = 3,298,532,681.28/78,091.70
6. Step 6: Final answer
   x = 42,239.22