Finding the Fourth Proportional to 1,100.53, 1,518.31 and 680.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,100.53 : 1,518.31 = 680.74 : x
2. Step 2: Convert to fraction form
   1,100.53/1,518.31 = 680.74/x
3. Step 3: Cross multiply
   1,100.53x = 1,518.31 × 680.74
4. Step 4: Simplify right side
   1,100.53x = 1,033,570.95
5. Step 5: Solve for x
   x = 1,033,570.95/1,100.53
6. Step 6: Final answer
   x = 939.16