Devide 45 into the ratio of 7:2

The way I do it is that I add the numbers of the ratio first (7+2=9) - this gives me a numnber of "units"

now, each Unit will be the number divided by this sum: 9.

so 45/9=5

so each unit is "5".

and the ratio will be the multiplication of this,

7*5=35
2*5=10

so the result will be 35:10