Finding the Fourth Proportional to 2,113.79, 3,171.30 and 653.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,113.79 : 3,171.30 = 653.18 : x
2. Step 2: Convert to fraction form
   2,113.79/3,171.30 = 653.18/x
3. Step 3: Cross multiply
   2,113.79x = 3,171.30 × 653.18
4. Step 4: Simplify right side
   2,113.79x = 2,071,429.73
5. Step 5: Solve for x
   x = 2,071,429.73/2,113.79
6. Step 6: Final answer
   x = 979.96