Finding the Fourth Proportional to 99.50, 137.33 and 58.05

Step by Step Solution

1. Step 1: Write the proportion equation
   99.50 : 137.33 = 58.05 : x
2. Step 2: Convert to fraction form
   99.50/137.33 = 58.05/x
3. Step 3: Cross multiply
   99.50x = 137.33 × 58.05
4. Step 4: Simplify right side
   99.50x = 7,971.89
5. Step 5: Solve for x
   x = 7,971.89/99.50
6. Step 6: Final answer
   x = 80.12