# Math Help - probability help

1. ## probability help

please can someone help me with this problem?

the 29 students in a primary school mixed class are all either year 2 students or year three students.
There ar ethe same number of yr two students in the class as as there are boys in the class.
There are 8 yr 2 boys in the class.
the number of yr 3 girls in the class exceeds the number of year 3 boys by 3.
how many yr 3 girls are there in this class?

I already know that I need to use a table for it, but I'm not too sure how to solve it!
any help would be great! thankyou=]

xxx
mariks

2. Originally Posted by xch3m_is_l0v3x
please can someone help me with this problem?

the 29 students in a primary school mixed class are all either year 2 students or year three students.
There ar ethe same number of yr two students in the class as as there are boys in the class.
There are 8 yr 2 boys in the class.
the number of yr 3 girls in the class exceeds the number of year 3 boys by 3.
how many yr 3 girls are there in this class?

I already know that I need to use a table for it, but I'm not too sure how to solve it!
any help would be great! thankyou=]

xxx
mariks
This has nothing to do with probability so I don't know why you would give your post the title it has.

Solve the following four equations simultaneously for $G_3$:

$B_2 + G_2 + B_3 + G_3 = 29$ .... (1)

$B_2 + G_2 = B_2 + B_3 \Rightarrow G_2 = B_3$ .... (2)

$B_2 = 8$ .... (3)

$G_3 = B_3 + 3$ .... (4)