Finding the Fourth Proportional to 99.57, 149.35 and 72.23

Step by Step Solution

1. Step 1: Write the proportion equation
   99.57 : 149.35 = 72.23 : x
2. Step 2: Convert to fraction form
   99.57/149.35 = 72.23/x
3. Step 3: Cross multiply
   99.57x = 149.35 × 72.23
4. Step 4: Simplify right side
   99.57x = 10,787.55
5. Step 5: Solve for x
   x = 10,787.55/99.57
6. Step 6: Final answer
   x = 108.34