Finding the Fourth Proportional to 1,139.67, 1,706.40 and 894.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.67 : 1,706.40 = 894.78 : x
2. Step 2: Convert to fraction form
   1,139.67/1,706.40 = 894.78/x
3. Step 3: Cross multiply
   1,139.67x = 1,706.40 × 894.78
4. Step 4: Simplify right side
   1,139.67x = 1,526,852.59
5. Step 5: Solve for x
   x = 1,526,852.59/1,139.67
6. Step 6: Final answer
   x = 1,339.73