Finding the Fourth Proportional to 1,143.30, 1,577.41 and 770.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,143.30 : 1,577.41 = 770.70 : x
2. Step 2: Convert to fraction form
   1,143.30/1,577.41 = 770.70/x
3. Step 3: Cross multiply
   1,143.30x = 1,577.41 × 770.70
4. Step 4: Simplify right side
   1,143.30x = 1,215,709.89
5. Step 5: Solve for x
   x = 1,215,709.89/1,143.30
6. Step 6: Final answer
   x = 1,063.33