Stem-and-leaf plots
question: how many swimmers were younger then 30
stem -- leaf
0
1-- 1
2-- 3,9
3 --
4 -- 7
5-- 5,7,7,9
6-- 5,5,6,6,7,8,9
7-- 0,1
key: 7-- 1 means 71

We are looking for any swimmer's whose age begins with a 0, 1 or 2.

We look at the tree and count one swimmer (age 11) beginning with a 1 and two swimmers (age 23 and 29) beginning with a two.

In total, there are three swimmers younger than 30.

goog may have it for you

b. 6

step-by-step explanation:

we are given the table representing an exponential function.

we can see from the table that, as x is increasing, the value of y is increasing in the power of 6.

i.e. the following relation is obtained,

x = 1, y = 6

x = 2, y = 36 =

x = 3, y = 216 =

x = 4, y = 1296 =

x = 5, y = 7776 =

so, the geometric series obtained is .

thus, the common ratio is given by = = 6.

hence, the common ratio is 6.