Finding the Fourth Proportional to 99.15, 136.83 and 74.55

Step by Step Solution

1. Step 1: Write the proportion equation
   99.15 : 136.83 = 74.55 : x
2. Step 2: Convert to fraction form
   99.15/136.83 = 74.55/x
3. Step 3: Cross multiply
   99.15x = 136.83 × 74.55
4. Step 4: Simplify right side
   99.15x = 10,200.70
5. Step 5: Solve for x
   x = 10,200.70/99.15
6. Step 6: Final answer
   x = 102.88