Finding the Fourth Proportional to 142.58, 196.66 and 100.50

Step by Step Solution

1. Step 1: Write the proportion equation
   142.58 : 196.66 = 100.50 : x
2. Step 2: Convert to fraction form
   142.58/196.66 = 100.50/x
3. Step 3: Cross multiply
   142.58x = 196.66 × 100.50
4. Step 4: Simplify right side
   142.58x = 19,764.33
5. Step 5: Solve for x
   x = 19,764.33/142.58
6. Step 6: Final answer
   x = 138.62