A shop sells packs of black pens, packs of red pens and packs of green pens.
There are
3
pens in each pack of black pens
5 pens in each pack of red pens
pens in each pack of green pens
On Monday,
number of packs number of packs
of black pens sold of red pens sold
=7:3:4
number of packs
of green pens sold
A total of 212 pens were sold.
Work out the number of green pens sold.