Answer:
Gabe needs 20 liters of the 40% solution.
He also needs 40 liters of the 70% solution.
Step-by-step explanation:
Equation:
acid + acid = acid
0.40x + 0.70(60-x) = 0.60*60
40x + 70*60 - 70x = 60*60
-30x = -10*60
x = 20 liters
Gabe needs 20 liters of the 40% solution.
He also needs 40 liters of the 70% solution.
The answer is 12 because it is a negative
Answer:
A
Step-by-step explanation:
12x12 = 144 per side
144x6 sides = 864
Answer:
Step-by-step explanation:
This is a good example of permutations. For the first slot on his shelf, Dylan has 7 trophies to choose from. Then 6, 5, and so on. Since he is only fitting 4 trophies on his shelf, we only continue until we have the slots filled. Thus, we have 
to do so.
*Note: We do not divide by 
because in this case, order matters. A different order of the same four books still produces different arrangements, so the order matters.
