Finding the Fourth Proportional to 99.50, 137.31 and 58.06

Step by Step Solution

1. Step 1: Write the proportion equation
   99.50 : 137.31 = 58.06 : x
2. Step 2: Convert to fraction form
   99.50/137.31 = 58.06/x
3. Step 3: Cross multiply
   99.50x = 137.31 × 58.06
4. Step 4: Simplify right side
   99.50x = 7,971.93
5. Step 5: Solve for x
   x = 7,971.93/99.50
6. Step 6: Final answer
   x = 80.12