Finding the Fourth Proportional to 78,321.45, 117,455.82 and 28,391.10

Step by Step Solution

1. Step 1: Write the proportion equation
   78,321.45 : 117,455.82 = 28,391.10 : x
2. Step 2: Convert to fraction form
   78,321.45/117,455.82 = 28,391.10/x
3. Step 3: Cross multiply
   78,321.45x = 117,455.82 × 28,391.10
4. Step 4: Simplify right side
   78,321.45x = 3,334,699,931.20
5. Step 5: Solve for x
   x = 3,334,699,931.20/78,321.45
6. Step 6: Final answer
   x = 42,577.10