Finding the Fourth Proportional to 3,699.64, 5,106.18 and 2,128.69

Step by Step Solution

1. Step 1: Write the proportion equation
   3,699.64 : 5,106.18 = 2,128.69 : x
2. Step 2: Convert to fraction form
   3,699.64/5,106.18 = 2,128.69/x
3. Step 3: Cross multiply
   3,699.64x = 5,106.18 × 2,128.69
4. Step 4: Simplify right side
   3,699.64x = 10,869,474.30
5. Step 5: Solve for x
   x = 10,869,474.30/3,699.64
6. Step 6: Final answer
   x = 2,937.98