Finding the Fourth Proportional to 105.42, 157.38 and 99.30

Step by Step Solution

1. Step 1: Write the proportion equation
   105.42 : 157.38 = 99.30 : x
2. Step 2: Convert to fraction form
   105.42/157.38 = 99.30/x
3. Step 3: Cross multiply
   105.42x = 157.38 × 99.30
4. Step 4: Simplify right side
   105.42x = 15,627.83
5. Step 5: Solve for x
   x = 15,627.83/105.42
6. Step 6: Final answer
   x = 148.24