Finding the Third Proportional to 1,131.75 and 1,312.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.75 : 1,312.31 = 1,312.31 : x
2. Step 2: Convert to fraction form
   1,131.75/1,312.31 = 1,312.31/x
3. Step 3: Cross multiply
   1,131.75x = 1,312.31 × 1,312.31
4. Step 4: Simplify right side
   1,131.75x = 1,722,164.10
5. Step 5: Solve for x
   x = 1,722,164.10/1,131.75
6. Step 6: Final answer
   x = 1,521.68