Finding the Fourth Proportional to 99.35, 136.88 and 78.62

Step by Step Solution

1. Step 1: Write the proportion equation
   99.35 : 136.88 = 78.62 : x
2. Step 2: Convert to fraction form
   99.35/136.88 = 78.62/x
3. Step 3: Cross multiply
   99.35x = 136.88 × 78.62
4. Step 4: Simplify right side
   99.35x = 10,761.45
5. Step 5: Solve for x
   x = 10,761.45/99.35
6. Step 6: Final answer
   x = 108.32