Finding the Fourth Proportional to 1,272.18, 1,755.57 and 774.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,272.18 : 1,755.57 = 774.72 : x
2. Step 2: Convert to fraction form
   1,272.18/1,755.57 = 774.72/x
3. Step 3: Cross multiply
   1,272.18x = 1,755.57 × 774.72
4. Step 4: Simplify right side
   1,272.18x = 1,360,075.19
5. Step 5: Solve for x
   x = 1,360,075.19/1,272.18
6. Step 6: Final answer
   x = 1,069.09