What is the next number in the sequence? 30,28,25,21,16,...

The sequence appears to be decreasing by an increasing amount each time.

The first difference between 30 and 28 is 2. The second difference between 28 and 25 is 3. The third difference between 25 and 21 is 4. The fourth difference between 21 and 16 is 5.

So, if the pattern continues, the next difference should be 6.

Subtracting 6 from the last number in the sequence (16) gives us 10.

So, the next number in the sequence should be 10.