Finding the Fourth Proportional to 99.18, 148.59 and 89.10

Step by Step Solution

1. Step 1: Write the proportion equation
   99.18 : 148.59 = 89.10 : x
2. Step 2: Convert to fraction form
   99.18/148.59 = 89.10/x
3. Step 3: Cross multiply
   99.18x = 148.59 × 89.10
4. Step 4: Simplify right side
   99.18x = 13,239.37
5. Step 5: Solve for x
   x = 13,239.37/99.18
6. Step 6: Final answer
   x = 133.49