Finding the Third Proportional to 412.59 and 859.78

Step by Step Solution

1. Step 1: Write the proportion equation
   412.59 : 859.78 = 859.78 : x
2. Step 2: Convert to fraction form
   412.59/859.78 = 859.78/x
3. Step 3: Cross multiply
   412.59x = 859.78 × 859.78
4. Step 4: Simplify right side
   412.59x = 739,223.80
5. Step 5: Solve for x
   x = 739,223.80/412.59
6. Step 6: Final answer
   x = 1,791.65