Finding the Fourth Proportional to 91.38, 137.13 and 90.62

Step by Step Solution

1. Step 1: Write the proportion equation
   91.38 : 137.13 = 90.62 : x
2. Step 2: Convert to fraction form
   91.38/137.13 = 90.62/x
3. Step 3: Cross multiply
   91.38x = 137.13 × 90.62
4. Step 4: Simplify right side
   91.38x = 12,426.72
5. Step 5: Solve for x
   x = 12,426.72/91.38
6. Step 6: Final answer
   x = 135.99