Finding the Fourth Proportional to 2,172.79, 2,998.47 and 1,178.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,172.79 : 2,998.47 = 1,178.09 : x
2. Step 2: Convert to fraction form
   2,172.79/2,998.47 = 1,178.09/x
3. Step 3: Cross multiply
   2,172.79x = 2,998.47 × 1,178.09
4. Step 4: Simplify right side
   2,172.79x = 3,532,467.52
5. Step 5: Solve for x
   x = 3,532,467.52/2,172.79
6. Step 6: Final answer
   x = 1,625.77