Finding the Fourth Proportional to 1,271.88, 1,910.79 and 785.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,271.88 : 1,910.79 = 785.34 : x
2. Step 2: Convert to fraction form
   1,271.88/1,910.79 = 785.34/x
3. Step 3: Cross multiply
   1,271.88x = 1,910.79 × 785.34
4. Step 4: Simplify right side
   1,271.88x = 1,500,619.82
5. Step 5: Solve for x
   x = 1,500,619.82/1,271.88
6. Step 6: Final answer
   x = 1,179.84