Finding the Fourth Proportional to 2,116.98, 3,172.12 and 1,421.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,116.98 : 3,172.12 = 1,421.10 : x
2. Step 2: Convert to fraction form
   2,116.98/3,172.12 = 1,421.10/x
3. Step 3: Cross multiply
   2,116.98x = 3,172.12 × 1,421.10
4. Step 4: Simplify right side
   2,116.98x = 4,507,899.73
5. Step 5: Solve for x
   x = 4,507,899.73/2,116.98
6. Step 6: Final answer
   x = 2,129.40