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

### Instruction:
Dana has 15 more pencils than Jayden, who has twice as much as Marcus. How many more pencils does Dana have than Marcus, if Jayden has 20 pencils?

### Response:
 Ikiwa Jayden ana madaftari 20, na Dana ana madaftari 15 zaidi ya Jayden, basi Dana ana madaftari 20+15 = <<20+15=35>>35.
Jayden ana madaftari 20, ambayo ni mara mbili ya Marcus, hivyo Marcus ana madaftari 20/2 = <<20/2=10>>10.
Idadi ya madaftari ambayo Dana ana zaidi ya Marcus ni 35-10 = <<35-10=25>>25.