Answer:
Cost ratio of pens:pencils = 9 : 4
Step-by-step explanation:
Pen : Pencil
10/10 : 12/12
22.5 / 10 : 18 / 12
2.25 : 1.5 cost per pen : pencil
HC of 0.25 and 0.5 is 8
8 x 2.25 = 18:
1.5 x 8 = 12
Then place them under their denominator x 10 x 12
pens = 18/10 = 1.8
pencils = 12/12 = 1
HC of 1.8 and 1 is 5
1.8 x 5 = 9
1 x 5 = 5
Answer = 9 : 4
