NEED HELP ASAP!

Of the rocks in a box, 1/3 are igneous, 60 are
metamorphic, and the remaining 40% are sedimentary.
How many rocks are in the box?

1= 160
2= 180
3= 200
4= 225

Respuesta :

4.) 225

1/3+4/10+60

1/15= 15

15*15= 225