Finding the Fourth Proportional to 100.50, 138.69 and 69.42

Step by Step Solution

1. Step 1: Write the proportion equation
   100.50 : 138.69 = 69.42 : x
2. Step 2: Convert to fraction form
   100.50/138.69 = 69.42/x
3. Step 3: Cross multiply
   100.50x = 138.69 × 69.42
4. Step 4: Simplify right side
   100.50x = 9,627.86
5. Step 5: Solve for x
   x = 9,627.86/100.50
6. Step 6: Final answer
   x = 95.80