Finding the Fourth Proportional to 99.98, 138.24 and 89.06

Step by Step Solution

1. Step 1: Write the proportion equation
   99.98 : 138.24 = 89.06 : x
2. Step 2: Convert to fraction form
   99.98/138.24 = 89.06/x
3. Step 3: Cross multiply
   99.98x = 138.24 × 89.06
4. Step 4: Simplify right side
   99.98x = 12,311.65
5. Step 5: Solve for x
   x = 12,311.65/99.98
6. Step 6: Final answer
   x = 123.14