Finding the Fourth Proportional to 109.02, 150.36 and 72.18

Step by Step Solution

1. Step 1: Write the proportion equation
   109.02 : 150.36 = 72.18 : x
2. Step 2: Convert to fraction form
   109.02/150.36 = 72.18/x
3. Step 3: Cross multiply
   109.02x = 150.36 × 72.18
4. Step 4: Simplify right side
   109.02x = 10,852.98
5. Step 5: Solve for x
   x = 10,852.98/109.02
6. Step 6: Final answer
   x = 99.55