Add
(i) (–40) and (30)
(ii) 60 and (–50)

A submarine is at 32 feet below the sea level. Then it moves up 8 feet. Find the depth of the submarine.

From the ground floor a man went up six floors and came down six floors. In which floor is he now?

Find the missing integers 
(i) 0 + (2345) =______
(ii) 23479 +  ______= 0

Find the value of :
(i) (-35)\(\times \) (-11) 
(ii) 96\(\times \)(-20) 
(iii) (-5)\(\times \)12 
(iv) 15\(\times \) 5 
(v) 999\(\times \)0