Respuesta :

mosunmolaajagbe

Step-by-step explanation:

A(promotional sign)b

A=kb

4=21k

K=0. 1904

A=0. 2b

A=0. 2×7

A=1. 4

josshyaby

:

Step-by-step explanation:

a varies directly with b

a ∞ b

a = Kb

K is the constant of proportionality

If a = 4 when b = 21

4 = 21×k

4 = 21k

k = 4/21

: - a = 4b/21

find a when b= 7.

a = 4(7)/21

a = 4/3

a = 1 1/3