Need help in number 22. Thanks for helping

3/15=2/n
Multiply up and down
3*n, 15*2= 3n and 30
Divide by 3 for 3n and 30
3n/3=30/3
n=10
Check answer by using substitution method
3/15=2/n
3/15=2/10
Reduce by 3 for 3/15, Reduce by 2 for 2/10
3/15=1/5
2/10= 1/5
Answer is n=10- G