In 2000, market shares of toilet soaps Margo, Palmolive and dove were 40%, 30% and 30% respectively. Starting from next year, a new soap enters into market each year and gets 10% of market share. The existing soap share remaining market share in same ratio as y did in previous year. What percent of total market share will mango have in 2002?

In 2000, the market share was 40%, 30% and 30%, means
the ratio is 4 : 3 : 3
In 2001, a new product (A) enters and has 10% market share, 90% of the remaining market is shared by the previous 3.
Now, divide 90% in the ratio 4 : 3 : 3 , i.e 36%, 27%, 27%.
Now the ratio is 36 : 27 : 27 : 10
In 2002, another new product (B) enters and has 10% market share, now the remaining 90% market share is distributed in the ratio,
36 : 27 : 27 : 10
and hence remaining 32.4%, 24.3%, 24.3%, 9%
Thus, the market share of Margo in 2002 is 32.4%