Finding the Fourth Proportional to 99.59, 137.18 and 88.53

Step by Step Solution

1. Step 1: Write the proportion equation
   99.59 : 137.18 = 88.53 : x
2. Step 2: Convert to fraction form
   99.59/137.18 = 88.53/x
3. Step 3: Cross multiply
   99.59x = 137.18 × 88.53
4. Step 4: Simplify right side
   99.59x = 12,144.25
5. Step 5: Solve for x
   x = 12,144.25/99.59
6. Step 6: Final answer
   x = 121.95