Mr. mckay bought b boxes of crackers for $3 each and p pounds of cheese for $4 per pound. how much did he spend in all?

The total amount he spend is:

                  $ (3b+4p)

It is given that:

Cost of 1 box of crackers= $ 3

This means that the cost of b boxes of crackers= $ 3b

Also,

Cost of 1 pound of cheese= $ 4

This means that the cost of p pounds of cheese= $ 4p

Hence, the total amount he spend=

Cost of b boxes of crackers+Cost of p pounds of cheese.

=   $ 3b+$ 4p

= $ (3b+4p)

b.-4 units

all you   do is count how many times you move