A teacher collects a total of 17 phones and iPods before a group of students head on a bushwalk. From a second group of students, 40 phones and iPods are collected. The second group had tqice the number of phones and 3 times the number of iPods than the first group. How many phones and iPods did the first group have?

Question

ajprincess · Answer

Let us assume that number of ipods the first group had be x nd number of phones be y.
then
x+y=17
3x+2y=40
Can u solve these simultaneous equations? @oly.surf

texaschic101 · Answer

it would be easier to solve by substitution :)

linyu · Answer

lets the first group be ax+by=17
second group be Ax+By=40
The sum of the whole groups (A+a)x+(B+b)y=57
We have a relation A/a=2 as to A=2a, B/b=3 as to B=3b
Therefore the total sum can be written as (2a+a)x+(3b+b)y=57
3ax+4by=57. a and b are just expressions for the relationship of first and second group so we delete them and write the first group and the sum equation
x+y=17
3x+4y=57
can you solve it?

mayankdevnani · Answer

by moving  towards the @ajprincess    method..
x+y=17
3x+2y=40

First solve. x+y=17
x=17-y

 and then put x=17-y in 3x+2y=40
3(17-y)+2y=40
can you solve it????    @oly.surf

mayankdevnani · Answer

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