Ratios

Question 1

What is ratios?

Answer 1

it is to compare the relative quantities of two or more things

also allows comparisons of groups of different sizes

Question 2

In Biology, what are ratios?

Answer 2

they are expressed as ?:1

1 represents the smallest number of the group

(we always use whole numbers)

i.e. 5:1 OR 0:2:1

Question 3

What always comes last in the 5:1 or ?:1 ratio?

Answer 3

the 1 always comes last

Question 4

E.g. of calculating ratios

red eyes = 78

blue eyes = 20

Calculate the ratio from red to blue

Answer 4

78/20 = 3.9
20/20 = 1

3.9:1

Question 5

E.g. of calculating multiple ratios

red = 127 
blue = 50 
green = 32
black = 8

Answer 5

127 / 8 = 15.875
50 / 8 = 6.25
32 / 8 = 4.0
8 / 8 = 1.0

15.9: 6.3 : 4.0 : 1.0

Question 6

What is the equation to work out the ratio of surface area to volume?

Answer 6

surface area / volume

can be expressed as x:1