Answer:
Associative property of addition
Let the number of chemistry books be x and the number of calculus books be y
total number of books in each case is:
x+y=24
x=24-y.....i
Weight of each case:
2707.2/20
=135.36
thus
4.2x+6.0y=135.36..ii substituting i in ii
4.2(24-y)+6y=135.36
100.8-4.2y+6y=135.36
hence
1.8y=34.56
y=19.2
hence
x=24-19.2
x=4.8
thus the number of chemistry books was 4.8*20=96 number of calculus was
19.2*20
=384 books
Answer:9
Step-by-step explanation:
12-9=3 12-3=9 3+9=12
So C=9
Let us assume that the number of alternative schools in the county are x in number.
It is given that the number of charter schools is 4 less than twice the number of alternative schools. So we can write, the number of charter schools is 4 less than twice of x. In equation form this can be written as:
Number of Charter Schools = 2x - 4
It is given that number of charter schools is 48. So we can write:
48 = 2x - 4
2x = 52
x = 26
x was the number of alternative schools. Therefore, there are 26 alternative schools in the county.
