Finding the Fourth Proportional to 131.38, 196.72 and 90.62

Step by Step Solution

1. Step 1: Write the proportion equation
   131.38 : 196.72 = 90.62 : x
2. Step 2: Convert to fraction form
   131.38/196.72 = 90.62/x
3. Step 3: Cross multiply
   131.38x = 196.72 × 90.62
4. Step 4: Simplify right side
   131.38x = 17,826.77
5. Step 5: Solve for x
   x = 17,826.77/131.38
6. Step 6: Final answer
   x = 135.69