Finding the Fourth Proportional to 78,742.70, 118,137.89 and 28,135.10

Step by Step Solution

1. Step 1: Write the proportion equation
   78,742.70 : 118,137.89 = 28,135.10 : x
2. Step 2: Convert to fraction form
   78,742.70/118,137.89 = 28,135.10/x
3. Step 3: Cross multiply
   78,742.70x = 118,137.89 × 28,135.10
4. Step 4: Simplify right side
   78,742.70x = 3,323,821,050.10
5. Step 5: Solve for x
   x = 3,323,821,050.10/78,742.70
6. Step 6: Final answer
   x = 42,211.17