A grocer wants to mix a type of spice which costs £22 per kilogram with another type which costs £12 per kilogram, to obtain 20 kilograms of mixture which will cost £15 per
kilogram. What quantity of each spice must the grocer take?

60

Step-by-step explanation:

let a = 22 / kg, and b = 12 / kg

a + b = 20 kg

22a + 12b = 15 * 20

12a + 12b = 240

10a = 60

isaiah walks 3 miles due north, turns and then 5 miles due east. how far is he from his starting point?

a^2 + b^2 = c^2

let c = distance from starting point.

(3)^2 + (5)^2 = c^2

9 + 25 = c^2

34 = c^2

sqrt{34} = sqrt{c^2}

sqrt{34} = c