Finding the Fourth Proportional to 1,919.55, 2,648.25 and 1,172.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,919.55 : 2,648.25 = 1,172.91 : x
2. Step 2: Convert to fraction form
   1,919.55/2,648.25 = 1,172.91/x
3. Step 3: Cross multiply
   1,919.55x = 2,648.25 × 1,172.91
4. Step 4: Simplify right side
   1,919.55x = 3,106,158.91
5. Step 5: Solve for x
   x = 3,106,158.91/1,919.55
6. Step 6: Final answer
   x = 1,618.17