Finding the Fourth Proportional to 92.82, 128.12 and 78.06

Step by Step Solution

1. Step 1: Write the proportion equation
   92.82 : 128.12 = 78.06 : x
2. Step 2: Convert to fraction form
   92.82/128.12 = 78.06/x
3. Step 3: Cross multiply
   92.82x = 128.12 × 78.06
4. Step 4: Simplify right side
   92.82x = 10,001.05
5. Step 5: Solve for x
   x = 10,001.05/92.82
6. Step 6: Final answer
   x = 107.75