Hey how are you doing today?
If you know that there are 21 members and 13 are females, if you subtract 13 from 21, you will get 8. There are 8 females in the gardening club.
Now you have to figure out the ratio to females to all club members. You already know that there are 8 females and 21 club members. The ratio would be 8:21.
I hope you found this helpful :)
Set as a proportion
16 = 12
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5x+2 24
cross multiply
12(5x+2) = 16 * 24
60x +24 = 384
60x +24-24 = 384-24
60x =360
60x/60=360/60
x =6
To figure AB plug 6 into 5x+2
5x +2
5(6) + 2
30+2
32
AB = 32