Finding the Fourth Proportional to 2,116.86, 2,921.41 and 1,172.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,116.86 : 2,921.41 = 1,172.69 : x
2. Step 2: Convert to fraction form
   2,116.86/2,921.41 = 1,172.69/x
3. Step 3: Cross multiply
   2,116.86x = 2,921.41 × 1,172.69
4. Step 4: Simplify right side
   2,116.86x = 3,425,918.63
5. Step 5: Solve for x
   x = 3,425,918.63/2,116.86
6. Step 6: Final answer
   x = 1,618.39