Finding the Fourth Proportional to 99.10, 136.72 and 65.96

Step by Step Solution

1. Step 1: Write the proportion equation
   99.10 : 136.72 = 65.96 : x
2. Step 2: Convert to fraction form
   99.10/136.72 = 65.96/x
3. Step 3: Cross multiply
   99.10x = 136.72 × 65.96
4. Step 4: Simplify right side
   99.10x = 9,018.05
5. Step 5: Solve for x
   x = 9,018.05/99.10
6. Step 6: Final answer
   x = 91.00