To do this multiply 1 by 4, then 3 by 5. 4 over 15 is your answer.
Answer:
Size of each group = 
Step-by-step explanation:
Total number of paint brushes = x
Since each the three groups are equally sized, to get the number of paintbrushes in a group, we will have to divide the total number of paint brushes by 3
∴ We have, number of paint brushes in a group = 
= 
this is also the same thing as saying
×
This shows that the size of the new group is the same as
the size of the original group
You just multiply 450 by .18 and it'll give you the 18% you have to add to 450.
So the equation would look like:
450(.18)=81
Which you then add:
450+81= 531
So 531 is your total!