Finding the Fourth Proportional to 99.50, 149.06 and 83.15

Step by Step Solution

1. Step 1: Write the proportion equation
   99.50 : 149.06 = 83.15 : x
2. Step 2: Convert to fraction form
   99.50/149.06 = 83.15/x
3. Step 3: Cross multiply
   99.50x = 149.06 × 83.15
4. Step 4: Simplify right side
   99.50x = 12,393.18
5. Step 5: Solve for x
   x = 12,393.18/99.50
6. Step 6: Final answer
   x = 124.56