Finding the Fourth Proportional to 91.62, 137.46 and 90.10

Step by Step Solution

1. Step 1: Write the proportion equation
   91.62 : 137.46 = 90.10 : x
2. Step 2: Convert to fraction form
   91.62/137.46 = 90.10/x
3. Step 3: Cross multiply
   91.62x = 137.46 × 90.10
4. Step 4: Simplify right side
   91.62x = 12,385.15
5. Step 5: Solve for x
   x = 12,385.15/91.62
6. Step 6: Final answer
   x = 135.18