Finding the Fourth Proportional to 105,476.21, 145,556.65 and 57,078.10

Step by Step Solution

1. Step 1: Write the proportion equation
   105,476.21 : 145,556.65 = 57,078.10 : x
2. Step 2: Convert to fraction form
   105,476.21/145,556.65 = 57,078.10/x
3. Step 3: Cross multiply
   105,476.21x = 145,556.65 × 57,078.10
4. Step 4: Simplify right side
   105,476.21x = 8,308,097,024.37
5. Step 5: Solve for x
   x = 8,308,097,024.37/105,476.21
6. Step 6: Final answer
   x = 78,767.50