Finding the Fourth Proportional to 90.94, 136.23 and 78.10

Step by Step Solution

1. Step 1: Write the proportion equation
   90.94 : 136.23 = 78.10 : x
2. Step 2: Convert to fraction form
   90.94/136.23 = 78.10/x
3. Step 3: Cross multiply
   90.94x = 136.23 × 78.10
4. Step 4: Simplify right side
   90.94x = 10,639.56
5. Step 5: Solve for x
   x = 10,639.56/90.94
6. Step 6: Final answer
   x = 117.00