Answer:
The number of green pens sold are 96 green pens
Explanation:
The given parameters for the packs of pens sold by the shop are;
The number of pens in each pack of black pens = 2 pens
The number of pens in each pack of red pens = 5 pens
The number of pens in each pack of green pens = 6 pens
The ratio of number of packs of pens sold Black : Red : Green = 7 : 3 : 4
The total number of pens sold = 212
Let 'x' represent the number of packs of pens sold
Therefore, the fraction of the packs the pens sold that are black pens = 7/(7 + 3 + 4) = 7/14 = 1/2
∴ 1/2 of the number of packs of pen sold = packs black pens = x/2
The fraction of the packs the pens sold that are red pens = 3/14
∴ 3/14 of the number of packs of pen sold = packs of red pens = 3·x/14
Similarly, we have;
The fraction of the packs the pens sold that are green pens = 4/14 = 2/7
∴ 2/7 of the number of packs of pen sold = packs of green pens = 2·x/7
Therefore, we have;
x/2 × 2 + 3·x/14 × 5 + 2·x/7 × 6 = 212
Where;
x/2 × 2 = The number of black pens sold
3·x/14 × 5 = The number of red pens sold
2·x/7 × 6 = The number of green pens sold
∴ 53·x/14 = 212
x = 212 × 14/53 = 56
∴ The number of packs of pens sold = x = 56 packs
The number of green pens sold = 2·x/7 × 6 = 2 × 56/7 × 6 = 96
The number of green pens sold = 96 pens.