Finding the Fourth Proportional to 2,167.34, 2,990.91 and 1,172.61

Step by Step Solution

1. Step 1: Write the proportion equation
   2,167.34 : 2,990.91 = 1,172.61 : x
2. Step 2: Convert to fraction form
   2,167.34/2,990.91 = 1,172.61/x
3. Step 3: Cross multiply
   2,167.34x = 2,990.91 × 1,172.61
4. Step 4: Simplify right side
   2,167.34x = 3,507,175.37
5. Step 5: Solve for x
   x = 3,507,175.37/2,167.34
6. Step 6: Final answer
   x = 1,618.20