Question

A teacher had 21 red pens. If the ratio of red pens to blue pens she owned was 3:1, how many pens did she have total? (just need work I have all answers just lost work please help this is due on fri.)

Answer 1

Ok so you do 3x7= 21 which you already know. So then you do 1x7=7. Last, you just add 21+7=28 pens in total