B 2/10 is not simplified because you can divide each number by 2 reducing it to 1/5.
Answer: 
Step-by-step explanation:
Given
It takes 20 min and 30 min for a person and his friend to paint a wall individually i.e.
In 1 min they cover
part and
part of wall respectively.
If the work together, 1 minute work is

Time required will be reciprocal of it

Answer:
LOL I NEED POINTS SORRY NOT SORRY
Step-by-step explanation:
<span>4−(2x+4)=5
4 - 2x - 4 = 5
-2x = 5
x = -5/2
x = - 2.5</span>
You need to go to school sorry I don’t know I just joined sorry