Answer:1.8(x -1)
2.0.4a -7
Step-by-step explanation:
I may not be able to use the appropriate vocabulary. But, the ratio of holiday stamps to president stamps is of 8:5 we can reach this conclusion because a ratio is just a fraction, if we put 40 over 25 we then put it in simplest form to get 8/5, or a ratio of 8 holiday stamps to every 5 president stamps
Setup
0.8x + 0.4y = 50
0.1x + 0.2y = 10 - Multiply by -2 and add
get
0.6x = 30
x = 50 mg compound A
.1 (50) + .2y = 10
5 + .2y = 10
.2y = 5
y = 25 mg compound B