Answer:
A) 3:9 => 1:3
B) 12:36 => 1:3
C) 13:39 => 1:3
D) 71:213 => 1:3
E) 142:213 => 2:3
F) 38:57 => 2:3
G) 33:44 => 3:4
H) 31:42 => 31:42 or 21:42 => 1:2
Step-by-step explanation:
The simplest form of the ratios are as follows:
A) 3:9
Dividing the ratio by 3
1:3
B) 12:36
Dividing the ratio by 12
1:3
C)13:39
Dividing the ratio by 13
1:3
D) 71:213
Dividing the ratio by 71
1:3
E) 142:213
Dividing the ratio by 71
2:3
F) 38:57
Dividing the ratio by 19
2:3
G) 33:44
Dividing the ratio by 11
3:4
H) 31:42
The ratio is already in simplest form as 31 and 42 don't have a common multiple.
Or it might be mistakenly typed 31 instead of 21
Then the simplest form will be:
21:42
1:2
Hence,
A) 3:9 => 1:2
B) 12:36 => 1:3
C) 13:39 => 1:3
D) 71:213 => 1:3
E) 142:213 => 2:3
F) 38:57 => 2:3
G) 33:44 => 3:4
H) 31:42 => 31:42 or 21:42 => 1:2
6 1/3 + k + 3 5/6 + 5 1/2 = 26 1/6
Add your fractions
6 1/3 + 3 5/6 + 5 1/2 = 15 2/3
now You need to isolate k on one side of the equation by using the subtraction method of equality.
k + 15 2/3 = 26 1/6
k = 10 1/2
Hope this helps
I had to edit
2) 
3) Opposite sides of a parallelogram are congruent.
4) 