Question

I need the answer to these, to be right, and you got to show the work on how you got the answer because if not I’ll get them wrong!! Thanks

Answer 1

 For question A
N is 20, Because 3 * 4 is 12 then multiply 4 to 5 too, and get 20
For question B it is 12 cause 7 * 6 is 42, then multiply it to 2 too, and it is 12
For Question C it is 1/2 = 50/100

Answer 2

A: $\frac{5}{3} = \frac{N}{12}$
Multiply both sides by 12
Answer: $N = 20$

B: $\frac{7}{2} = \frac{42}{N}$
Multiply both sides by 2, $7 = \frac{84}{N}$
Multiply both sides by N, $7N = 84$
Divide both sides by 7,
Answer: $N=12$

C: $\frac{N}{2}= \frac{50}{N}$
Multiply both sides by 2, $N = \frac{100}{N}$
Multiply both sides by N, $N^{2} = 100$
Simplify, 
Answer: $N = 10 , -10$

Hope I helped you!