Finding the Fourth Proportional to 2,212.18, 3,316.32 and 1,172.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,212.18 : 3,316.32 = 1,172.91 : x
2. Step 2: Convert to fraction form
   2,212.18/3,316.32 = 1,172.91/x
3. Step 3: Cross multiply
   2,212.18x = 3,316.32 × 1,172.91
4. Step 4: Simplify right side
   2,212.18x = 3,889,730.37
5. Step 5: Solve for x
   x = 3,889,730.37/2,212.18
6. Step 6: Final answer
   x = 1,758.33