Finding the Fourth Proportional to 99.50, 149.36 and 53.96

Step by Step Solution

1. Step 1: Write the proportion equation
   99.50 : 149.36 = 53.96 : x
2. Step 2: Convert to fraction form
   99.50/149.36 = 53.96/x
3. Step 3: Cross multiply
   99.50x = 149.36 × 53.96
4. Step 4: Simplify right side
   99.50x = 8,058.45
5. Step 5: Solve for x
   x = 8,058.45/99.50
6. Step 6: Final answer
   x = 80.99