Finding the Fourth Proportional to 99.77, 149.72 and 72.63

Step by Step Solution

1. Step 1: Write the proportion equation
   99.77 : 149.72 = 72.63 : x
2. Step 2: Convert to fraction form
   99.77/149.72 = 72.63/x
3. Step 3: Cross multiply
   99.77x = 149.72 × 72.63
4. Step 4: Simplify right side
   99.77x = 10,873.80
5. Step 5: Solve for x
   x = 10,873.80/99.77
6. Step 6: Final answer
   x = 108.99