Finding the Third Proportional to 3,980 and 5,990

Step by Step Solution

1. Step 1: Write the proportion equation
   3,980 : 5,990 = 5,990 : x
2. Step 2: Convert to fraction form
   3,980/5,990 = 5,990/x
3. Step 3: Cross multiply
   3,980x = 5,990 × 5,990
4. Step 4: Simplify right side
   3,980x = 35,880,100
5. Step 5: Solve for x
   x = 35,880,100/3,980
6. Step 6: Final answer
   x = 9,015.10