Observe the following tables and find if x and y are directly proportional.

(i)

X	20	17	14	11	8	5	2
y	40	34	28	22	16	10	4

(ii)

X	6	10	14	18	22	26	30
y	4	8	12	16	20	24	28

(iii)

X	5	8	12	15	18	20
y	15	24	36	60	72	100

In question 2 above, if 1 part of a red pigment requires 75 mL of base, how much red pigment should we mix with 1800 mL of base?

If we fix time period and the rate of interest, simple interest changes proportionally with principal. Would there be a similar relationship for compound interest? Why?

Following are the car parking charges near a railway station upto

A mixture of paint is prepared by mixing 1 part of red pigments with 8 parts of base. In the following table, find the parts of base that need to be added.