Finding the Third Proportional to 1,056.75 and 1,215.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,056.75 : 1,215.38 = 1,215.38 : x
2. Step 2: Convert to fraction form
   1,056.75/1,215.38 = 1,215.38/x
3. Step 3: Cross multiply
   1,056.75x = 1,215.38 × 1,215.38
4. Step 4: Simplify right side
   1,056.75x = 1,477,136.39
5. Step 5: Solve for x
   x = 1,477,136.39/1,056.75
6. Step 6: Final answer
   x = 1,397.81