Finding the Third Proportional to 1,131.19 and 2,215.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.19 : 2,215.69 = 2,215.69 : x
2. Step 2: Convert to fraction form
   1,131.19/2,215.69 = 2,215.69/x
3. Step 3: Cross multiply
   1,131.19x = 2,215.69 × 2,215.69
4. Step 4: Simplify right side
   1,131.19x = 4,909,271.10
5. Step 5: Solve for x
   x = 4,909,271.10/1,131.19
6. Step 6: Final answer
   x = 4,339.93