Finding the Fourth Proportional to 98.98, 136.71 and 78.49

Step by Step Solution

1. Step 1: Write the proportion equation
   98.98 : 136.71 = 78.49 : x
2. Step 2: Convert to fraction form
   98.98/136.71 = 78.49/x
3. Step 3: Cross multiply
   98.98x = 136.71 × 78.49
4. Step 4: Simplify right side
   98.98x = 10,730.37
5. Step 5: Solve for x
   x = 10,730.37/98.98
6. Step 6: Final answer
   x = 108.41