Answer:
x=2/15
Step-by-step explanation:
1/5+x+2/3=1
3/15+x+10/15=15/15
13/15+x=15/15
x=2/15
Its 20 the sides are equal
I think for number 3, it is the third option.
10 is not a multiple of 3 so no 6/10 is not multiples for 3/10 and 6 is not a mutiple of 10 so it can't be also the same with 6/30 although 6/30 is multiples for 3 but 6 is not a mutiple for 10.