 
 <prompt> Mark na 18 years old. E get small brother wey im name na John, wey dey 10 years younger. If John and Mark parents dey 5 times older pass John, how old dem be when Mark bin dey born? <response>: ```John na 8 years old because 18-10=8 years old.
Dem parents dey 40 years old because 8*5=40.
So, dem bin dey 22 years old wen Mark bin dey born because 40-18 = 22 years old.

The final answer: 22.``` 