Finding the Fourth Proportional to 106.18, 146.31 and 100.69

Step by Step Solution

1. Step 1: Write the proportion equation
   106.18 : 146.31 = 100.69 : x
2. Step 2: Convert to fraction form
   106.18/146.31 = 100.69/x
3. Step 3: Cross multiply
   106.18x = 146.31 × 100.69
4. Step 4: Simplify right side
   106.18x = 14,731.95
5. Step 5: Solve for x
   x = 14,731.95/106.18
6. Step 6: Final answer
   x = 138.75