Comparing correspodning elements from two different matrices with different dimensions

I have these two tables and I'm trying to look up the price of each ID from table A to add it to table B in order to calculate the discounted price, I've tried using vectorised codes but I'm struggling with the matrices dimensions as they aren't equal.

A=

ID Price

1 50

2 60

3 70

B=

CuID ID Discount

4 1 10

5 2 20

6 3 30

4 3 40

5 2 50

6 1 60

[Mohammad Sami]

You want to use the ismember function to find the corresponding rows in A using the ID in B