Finding the Fourth Proportional to 1,279.30, 1,763.81 and 836.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,279.30 : 1,763.81 = 836.50 : x
2. Step 2: Convert to fraction form
   1,279.30/1,763.81 = 836.50/x
3. Step 3: Cross multiply
   1,279.30x = 1,763.81 × 836.50
4. Step 4: Simplify right side
   1,279.30x = 1,475,418.25
5. Step 5: Solve for x
   x = 1,475,418.25/1,279.30
6. Step 6: Final answer
   x = 1,153.31