Lucy uses a code to open a lock. The code is a letter followed by a 2-digit number.
The letter is L or U.
The number is a prime number between 20 and 30
Write down all the possibilities for Lucy's code.

L23

L29

U23

U29

Step-by-step explanation:

We have two elements for the code:

Letter: The options are L and U.

Number: A prime number between 20 and 30, the options here are:

23, 29 (These are the only two prime numbers between 20 and 30)

Then the possible combinations are:

L23

L29

U23

U29

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