Answer:
56 ways
Step-by-step explanation:
Number of ways is given by n combination r (n!/(n - r)!r!)
n = total number of students = 8, r = the number of summer courses = 3
Number of ways = 8 combination 3 = 8!/(8-3)!3! = 8!/5!3! = 8×7×6×5!/5!×6 = 8×7 = 56 ways
Let 
be the volume of 20% solution, 
the volume of the 60% solution. We want a total volume of 400 mL in the final mixture, so
Each mL of either solution will contribute a corresponding concentration, and in the final mixture we want the 400 mL to have a 40% concentration, which means we should also have
Solve the system and we get 
.
Answer:
66 cm^2
Step-by-step explanation:
12*6=72 cm^2 and to find the missing pience of the rectangle you multiply 3*2= 6 cm^2.
72 - 6 = 66
Answer: 2+2=4 lol
Step-by-step explanation:
1+1=2
2+2=4
Answer:
x =60 ° angles on a straight line
y+25° =120° exterior angle of the triangle
y=120°-25°=95°
y =95 °
