You can download the NCERT solutions for Science mathematics and other subjects on the mentioned below link. You need to just click on the link and scroll down and you will find chapter wise NCERT solutions links. In the mentioned below link you will find links of not only from class 6 to 9th but also of 10th, 11th and 12th classes. Along with questions you will also find the links of answers of all the questions :

https://www.google.com/url?sa=t&source=web&rct=j&url=https://school.careers360.com/ncert/ncert-solutions&ved=2ahUKEwiFh4Pk_p73AhWSSmwGHTWBDfEQFnoECAwQAQ&usg=AOvVaw2zgvgUFG2XmZY0t98ylMc8