Finding the Fourth Proportional to 76,786.80, 105,974.36 and 42,798.39

Step by Step Solution

1. Step 1: Write the proportion equation
   76,786.80 : 105,974.36 = 42,798.39 : x
2. Step 2: Convert to fraction form
   76,786.80/105,974.36 = 42,798.39/x
3. Step 3: Cross multiply
   76,786.80x = 105,974.36 × 42,798.39
4. Step 4: Simplify right side
   76,786.80x = 4,535,531,538.38
5. Step 5: Solve for x
   x = 4,535,531,538.38/76,786.80
6. Step 6: Final answer
   x = 59,066.56