Red to Black. 2 to 3. For every 2 red we have 3 black so For 4 red we have 6 black and so on.. Notice that For every 2+3=5 pens we have 2 red ones If we divide the total number of pens 60 into groups of 5 we will get 60 /5= 12 groups. 12 groups •2 red pens=24 red pens
