human
A jar contains 9 blue pens, 21 black pens, and 6 red pens. Four blue pens are removed and then seven black pens are removed. How many pens are left in the jar?
assistant
How many blue pens are left in the jar? ** There are 9-4 = <<9-4=5>>5 blue pens left in the jar.
How many black pens are left in the jar? ** There are 21-7 = <<21-7=14>>14 black pens left in the jar.
How many pens are left in the jar? ** There are 5+14+6 = <<5+14+6=25>>25 pens left in the jar.
#### 25