Finding the Third Proportional to 2,978 and 5,380

Step by Step Solution

1. Step 1: Write the proportion equation
   2,978 : 5,380 = 5,380 : x
2. Step 2: Convert to fraction form
   2,978/5,380 = 5,380/x
3. Step 3: Cross multiply
   2,978x = 5,380 × 5,380
4. Step 4: Simplify right side
   2,978x = 28,944,400
5. Step 5: Solve for x
   x = 28,944,400/2,978
6. Step 6: Final answer
   x = 9,719.41