Finding the Fourth Proportional to 78.17, 107.82 and 67.79

Step by Step Solution

1. Step 1: Write the proportion equation
   78.17 : 107.82 = 67.79 : x
2. Step 2: Convert to fraction form
   78.17/107.82 = 67.79/x
3. Step 3: Cross multiply
   78.17x = 107.82 × 67.79
4. Step 4: Simplify right side
   78.17x = 7,308.92
5. Step 5: Solve for x
   x = 7,308.92/78.17
6. Step 6: Final answer
   x = 93.50