Finding the Fourth Proportional to 1,390.89, 2,085.41 and 834.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.89 : 2,085.41 = 834.34 : x
2. Step 2: Convert to fraction form
   1,390.89/2,085.41 = 834.34/x
3. Step 3: Cross multiply
   1,390.89x = 2,085.41 × 834.34
4. Step 4: Simplify right side
   1,390.89x = 1,739,940.98
5. Step 5: Solve for x
   x = 1,739,940.98/1,390.89
6. Step 6: Final answer
   x = 1,250.96