Finding the Fourth Proportional to 109.72, 151.33 and 78.67

Step by Step Solution

1. Step 1: Write the proportion equation
   109.72 : 151.33 = 78.67 : x
2. Step 2: Convert to fraction form
   109.72/151.33 = 78.67/x
3. Step 3: Cross multiply
   109.72x = 151.33 × 78.67
4. Step 4: Simplify right side
   109.72x = 11,903.98
5. Step 5: Solve for x
   x = 11,903.98/109.72
6. Step 6: Final answer
   x = 108.50