Finding the Fourth Proportional to 100,111.96, 138,185.34 and 57,698.80

Step by Step Solution

1. Step 1: Write the proportion equation
   100,111.96 : 138,185.34 = 57,698.80 : x
2. Step 2: Convert to fraction form
   100,111.96/138,185.34 = 57,698.80/x
3. Step 3: Cross multiply
   100,111.96x = 138,185.34 × 57,698.80
4. Step 4: Simplify right side
   100,111.96x = 7,973,128,295.59
5. Step 5: Solve for x
   x = 7,973,128,295.59/100,111.96
6. Step 6: Final answer
   x = 79,642.12