A )
−
1
21
+
−
1
28
;

b
)
−
8
18
−
15
27
;
c
)
−
5
12
+
0
,
75
;
d
)
3
,
5
−
(
−
2
7
)

"exterior angles = 360 / number of sides.

60 = 360 / sides

sides = 360 / 60

sides = 6"

fabric (square meters)                   cloaks

7                                                           21

4/3                                                         4

step-by-step explanation:

we are told that harry needs 2 square meters of fabric for every 6 wizard cloaks he makes.

1. first of all we will find how many cloaks can be made from 1 square meter of fabric by dividing 6 by 2.

we can see that 3 cloaks can be made from 1 square meter of fabric. now we will multiply 3 by 7 to find number of cloaks made from 7 square meters of fabric.

therefore, harry will make 21 cloaks from 7 square meters of fabric.

2. let us find how many square meters of fabric will be needed to make 4 cloaks.

first of all we will find fabric needed for 1 cloak by dividing 2 by 6.

we can see that fabric needed for 1 cloak is   square meter. now we will multiply   by 4 to find fabric needed for 4 cloaks.

any of them that add up to 180 degrees.