Finding the Fourth Proportional to 109.69, 151.50 and 72.78

Step by Step Solution

1. Step 1: Write the proportion equation
   109.69 : 151.50 = 72.78 : x
2. Step 2: Convert to fraction form
   109.69/151.50 = 72.78/x
3. Step 3: Cross multiply
   109.69x = 151.50 × 72.78
4. Step 4: Simplify right side
   109.69x = 11,026.27
5. Step 5: Solve for x
   x = 11,026.27/109.69
6. Step 6: Final answer
   x = 100.52