Respuesta :
Answer:
Probability of choosing two different types of biscuits is [tex]\frac{31}{90}[/tex].
Step-by-step explanation:
We have 10 biscuits in a tin.
There are 5 digestive, 3 chocolate, 2 ginger.
Steve takes two biscuits at random.
There are three combinations of biscuits.
P(d, c) + P(c,g)+P(d,g)
Let's find probability of each.
P(d,c)= P(d)* p(c)
= [tex]\frac{5}{10}*\frac{3}{9}[/tex]
Let's simplify it, we get [tex]\frac{1}{6}[/tex]
Like so, for P(c,g)
P(c,g)= P(c) * P(g)
=[tex]\frac{3}{10}*\frac{2}{9}[/tex]
Let's multiply and simplify, we get [tex]\frac{1}{15}[/tex].
Now, for p(d,g)
P(d, g)= P(d)* p(g)
=[tex]\frac{5}{10} *\frac{2}{9}[/tex]
Let's simplify and multiply, we get [tex]\frac{1}{9}[/tex].
Now, add them together
[tex]\frac{1}{6} +\frac{1}{15} +\frac{1}{9}[/tex]
Now, find LCD to make the denominators as same and then add them together.
LCD is 90
So, find equivalent fraction of each which has denominator as 90.
[tex]\frac{15}{90}+\frac{6}{90} +\frac{10}{90}[/tex] = [tex]\frac{31}{90}[/tex]
