Finding the Third Proportional to 1,120 and 1,380

Step by Step Solution

1. Step 1: Write the proportion equation
   1,120 : 1,380 = 1,380 : x
2. Step 2: Convert to fraction form
   1,120/1,380 = 1,380/x
3. Step 3: Cross multiply
   1,120x = 1,380 × 1,380
4. Step 4: Simplify right side
   1,120x = 1,904,400
5. Step 5: Solve for x
   x = 1,904,400/1,120
6. Step 6: Final answer
   x = 1,700.36