Finding the Fourth Proportional to 72.78, 109.32 and 69.96

Step by Step Solution

1. Step 1: Write the proportion equation
   72.78 : 109.32 = 69.96 : x
2. Step 2: Convert to fraction form
   72.78/109.32 = 69.96/x
3. Step 3: Cross multiply
   72.78x = 109.32 × 69.96
4. Step 4: Simplify right side
   72.78x = 7,648.03
5. Step 5: Solve for x
   x = 7,648.03/72.78
6. Step 6: Final answer
   x = 105.08