Finding the Fourth Proportional to 2,112.79, 3,168.90 and 651.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,112.79 : 3,168.90 = 651.91 : x
2. Step 2: Convert to fraction form
   2,112.79/3,168.90 = 651.91/x
3. Step 3: Cross multiply
   2,112.79x = 3,168.90 × 651.91
4. Step 4: Simplify right side
   2,112.79x = 2,065,837.60
5. Step 5: Solve for x
   x = 2,065,837.60/2,112.79
6. Step 6: Final answer
   x = 977.78