Answer:

Step-by-step explanation:
As given
if n erasers have a weight of 80 grams .
I.e
n erasera = 80 grams.
1 erasers weight .

Now find out the weight of the 50 erasers.

Simplify the above


Answer:19/20
1-20=19
1÷20=0.05
0.05=5%
I hope this is good enough:
I think you count the squares in the middle or radius ?
first you have to find the triangle, then you can move to the actual question.
x+30+80 = 180
x+110 = 180
x+110 - 110 = 180-110
x =70
now you can go to the actual question.
y + 70 = 180
y+70- 70 = 180-70
y = 110
there is your answer. hope this is helpful