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

Find the vertex of the function given below y=x^2-6x+1

Factor -8x3-2x2-12x-3 by grouping what is the resulting expression?

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.