Question 908078
45+1.75p+4.25c=75*3
45*+1.75p+4.25c=225
1.75p+4.25c=180
p+c=67
Since there will be 75 lbs and you already have 8 lbs, you need 67 lbs of peanuts and cashews.

x+y=67,
1.75*x+4.25*y=180
x=67-y
1.75*(67-y)+4.25*y=180
117.25-1.75y+4.25*y=180
2.5*y=62.75
y=25.1 
x=67-y
peanuts x=41.9 at 1.75 and  cashews y=25.1 at 4.25
check
41.9+25.1=67
1.75*x+4.25*y=180
1.75*41.9+4.25*25.1=180
73.325+106.675=180
180.0=180
ok