Finding the Fourth Proportional to 78.06, 107.71 and 67.12

Step by Step Solution

1. Step 1: Write the proportion equation
   78.06 : 107.71 = 67.12 : x
2. Step 2: Convert to fraction form
   78.06/107.71 = 67.12/x
3. Step 3: Cross multiply
   78.06x = 107.71 × 67.12
4. Step 4: Simplify right side
   78.06x = 7,229.50
5. Step 5: Solve for x
   x = 7,229.50/78.06
6. Step 6: Final answer
   x = 92.61