Question

please tellllllllllllllllllllllll

Answer 1

X = total quantity of ore,

12 % of that ore is copper:

= (x*12)/100 = 69
= 12x/100 = 69
= 3x/25 = 69
= 3x = 69*25
= 3x = 1725
= x = 1725/3
= x = 575 kg

575 kg ore is required to get 69 kg of copper.