Always teacher gave her science test with 25 questions on it she scored 80% on the test how many questions did she answer incorrectly

She got 5 incorrect.

Step-by-step explanation:

In order to find this, we start by using the formula for percentage.

Correct/Total = Percentage

Now we put in known quantities.

Correct/25 = .8

Now to solve we multiply both sides by 25

Correct = 20

Since she got 20 correct, we know she got 5 incorrect

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b