We would need 7 more squares in order to get 80%. Thus, 52% of the grid is shaded.
What is the unitary method?
The unitary method is a method for solving a problem by the first value of a single unit and then finding the value by multiplying the single value.
There are 25 boxes. we want to figure out how much each box is worth.
So,
100 / 25 = 4
Now, we know how much each box is worth.
There are 13 boxes shaded in,
so 13 x 4 = 52.
Keep adding boxes in order to get 80%.
For example, 52%, 56%, 60%.
Learn more about the unitary method;
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