Finding the Fourth Proportional to 131.50, 181.78 and 120.10

Step by Step Solution

1. Step 1: Write the proportion equation
   131.50 : 181.78 = 120.10 : x
2. Step 2: Convert to fraction form
   131.50/181.78 = 120.10/x
3. Step 3: Cross multiply
   131.50x = 181.78 × 120.10
4. Step 4: Simplify right side
   131.50x = 21,831.78
5. Step 5: Solve for x
   x = 21,831.78/131.50
6. Step 6: Final answer
   x = 166.02