Question

R varies directly as s. Find r when s=10 and k=4

Answer 1

40

Explanation:

r = ks = 4(10) = 40

Answer 2

Explanation:

Since, r varies directly as s

`\therefore \: r \: \: \alpha \: \: s \\ \therefore \: r = k s..(1) \: \\ (k = \: constant \: of \: proportionality ) \\ plug \: s = 10 \: and \: k = 4 \: in \: equation \: (1) \\ r = 4 * 10 \\ \huge \red{ \boxed{ \therefore \: r =40}}`