Finding the Third Proportional to 1,080.56 and 1,279.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,080.56 : 1,279.69 = 1,279.69 : x
2. Step 2: Convert to fraction form
   1,080.56/1,279.69 = 1,279.69/x
3. Step 3: Cross multiply
   1,080.56x = 1,279.69 × 1,279.69
4. Step 4: Simplify right side
   1,080.56x = 1,637,600.10
5. Step 5: Solve for x
   x = 1,637,600.10/1,080.56
6. Step 6: Final answer
   x = 1,515.51