Below is an instruction that describes a task. Write a response that appropriately completes the request in Swahili. Please answer in Swahili.

### Instruction:
Lenny bought 20 boxes of pens. Each box contained  5 pens. She gave 40% of the pens to her close friends and one-fourth of what's left to her classmates. How many pens were left for Lenny?

### Response:
 Lenny ana kalamu 20 x 5 = <<20*5=100>>100.
Aliwapa marafiki zake wa karibu kalamu 100 x 40% = <<100*40*.01=40>>40.
Hivyo, zilisalia kalamu 100 - 40 = <<100-40=60>>60.
Nusu ya 60 ni 60 x 1/4 = 15 kalamu.
Hivyo, zilisalia kalamu 60 - 15 = <<60-15=45>>45 kwa Lenny.