Finding the Fourth Proportional to 102.77, 141.82 and 78.16

Step by Step Solution

1. Step 1: Write the proportion equation
   102.77 : 141.82 = 78.16 : x
2. Step 2: Convert to fraction form
   102.77/141.82 = 78.16/x
3. Step 3: Cross multiply
   102.77x = 141.82 × 78.16
4. Step 4: Simplify right side
   102.77x = 11,084.10
5. Step 5: Solve for x
   x = 11,084.10/102.77
6. Step 6: Final answer
   x = 107.86