Please help! I am giving you 10 points for it!

So if John gives a pen and pencil to each and all of them are over we know that the no. of pencils and pens should be the same
So we will find the LCM of 15 and 40 that is equal to 120
So John brought 120/15 that is 8 packets of pen and 120/40 that is three packets of pencils

ANSWER:
If John gives one pen and one pencil to each then the no. Of pens and pencils should be same. Then LCM of 40 and 15 is 120 .
So,Jonh bought 40/120 =3 packets of box and 15/120 =8 packets of pencils.
HOPE IT HELPS

20y5 times 2 is 1010 times -2 is -20, plus y