What should be added to to obtain the nearest natural number?

Find a rational number exactly halfway between:

A.

B.

C.

D.

Taking and find :

(a) the rational number which when added to x gives y.

(b) the rational number which subtracted from y gives z.

(c) the rational number which when added to z gives us x.

(d) the rational number which when multiplied by y to get x.

(e) the reciprocal of x + y.

(f) the sum of reciprocals of x and y.

(g) (x ÷ y) × z

(h) (x – y) + z

(i) x + (y + z)

(j) x ÷ (y ÷ z)

(k) x – (y + z)

What should be subtracted fromto obtain the nearest integer?

What should be multiplied withto obtain the nearest integer?