Finding the Fourth Proportional to 2,211.78, 3,319.59 and 1,172.53

Step by Step Solution

1. Step 1: Write the proportion equation
   2,211.78 : 3,319.59 = 1,172.53 : x
2. Step 2: Convert to fraction form
   2,211.78/3,319.59 = 1,172.53/x
3. Step 3: Cross multiply
   2,211.78x = 3,319.59 × 1,172.53
4. Step 4: Simplify right side
   2,211.78x = 3,892,318.86
5. Step 5: Solve for x
   x = 3,892,318.86/2,211.78
6. Step 6: Final answer
   x = 1,759.81