Finding the Fourth Proportional to 72.16, 107.68 and 67.56

Step by Step Solution

1. Step 1: Write the proportion equation
   72.16 : 107.68 = 67.56 : x
2. Step 2: Convert to fraction form
   72.16/107.68 = 67.56/x
3. Step 3: Cross multiply
   72.16x = 107.68 × 67.56
4. Step 4: Simplify right side
   72.16x = 7,274.86
5. Step 5: Solve for x
   x = 7,274.86/72.16
6. Step 6: Final answer
   x = 100.82