Respuesta :

BladeOfTheMoon
The probability of selecting a black or blue pen is 4 out of 13. You calculate this by adding the amount of pens together and comparing it to the total amount of pens and pencils in the cup.
4 out of 13 because in total there are 13 supplies in all and if you add 3 black pens PLUS 1 blue pen that will be 4.