Finding the Fourth Proportional to 1,433.95, 1,978.85 and 836.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,433.95 : 1,978.85 = 836.80 : x
2. Step 2: Convert to fraction form
   1,433.95/1,978.85 = 836.80/x
3. Step 3: Cross multiply
   1,433.95x = 1,978.85 × 836.80
4. Step 4: Simplify right side
   1,433.95x = 1,655,898.82
5. Step 5: Solve for x
   x = 1,655,898.82/1,433.95
6. Step 6: Final answer
   x = 1,154.78