The number of 10 chips stacks that Dave can make if two stacks are not considered distinct is 110.
The solution
To get the symmetric stacks, one has to subtract the symmetric stacks to know the ones that are asymmetric.
The symmetric are flipped. Given that they are double counted what we have to do is to divide through by 2.
6/2 = 3
10/2 = 5
4/2 = 2
1/2(10C6) - (5C3) + (5C3)
0.5(210-10+10)
= 110
Let t and s represent the masses of 20% and 60% alloys respectively.
t+s=80, s=80-t
(0.2t+0.6s)/80=0.52 multiply both sides by 80
0.2t+0.6s=41.6, now using s=80-t in this equation gives us:
0.2t+0.6(80-t)=41.6 perform indicated multiplication on left side
0.2t+48-0.6t=41.6 combine like terms on left side
-0.4t+48=41.6 subtract 48 from both sides
-0.4t=-6.4 divide both sides by -0.4
t=16, since s=80-t
s=64
So 16kg of 20% alloy is mixed with 64kg of 60% allow to make 80kg of a 52% alloy.
Angle R is congruent to Angle Y
Side QR is congruent to side XY
