Stuart is buying a pair of jeans that regularly cost $40. they are on sale for 20% off. if the tax rate is 8%, what is the sale price of the jeans including tax?
a. $21.60
b. $34.56
c. $42.34
d. $44.16

answer: a

step-by-step explanation:

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