Finding the Fourth Proportional to 109.31, 163.16 and 100.18

Step by Step Solution

1. Step 1: Write the proportion equation
   109.31 : 163.16 = 100.18 : x
2. Step 2: Convert to fraction form
   109.31/163.16 = 100.18/x
3. Step 3: Cross multiply
   109.31x = 163.16 × 100.18
4. Step 4: Simplify right side
   109.31x = 16,345.27
5. Step 5: Solve for x
   x = 16,345.27/109.31
6. Step 6: Final answer
   x = 149.53