Ratio question

[Ehands1221]

Hello,

I am a older learner working through an school level maths book.

I am getting my knickers in a twist over question 10).

I simply do not know where to begin, if someone could point me in the right direction that would be appreciated.

 

[Deleted member 4993]

Hello,

I am a older learner working through an school level maths book. I am getting my knickers in a twist over question 10). I simply do not know where to begin, if someone could point me in the right direction that would be appreciated.

You need to find:

#of boys originally at the bus stop and​

​

#of girls originally at the bus stop​

So let:

#of boys originally at the bus stop = B​

​

#of girls originally at the bus stop = G​

You have two unknowns - so you need to find at least two equations to solve

then you have :

\(\displaystyle \frac{G - 25}{B} = \frac{2}{3}\)​

This is your first equation. From the statement of the problem find the second equation and solve....

Please share your work so that we know exactly where we should provide help.

 

[Ehands1221]

This is what I got. The text book states there should be 100 people. If there are 105 girls then this makes it impossible.

 

[Dr.Peterson]

Your second equation forgot that there are now G-25 girls at the stop, not G.

 

[Deleted member 4993]

This is what I got. The text book states there should be 100 people. If there are 105 girls then this makes it impossible.

Since 15 boys got on the second bus (we had G-25 girls there) - the second equation would be:

B - 15 = G - 25...........continue........

 

[Steven G]

As pointed out your 2nd equation is wrong. So fix that before moving on.

You made other mistakes after getting the wrong 2nd equation which I will like to comment on.

You had G - B = -15. NOT all the signs are the same (G is +, while -B and -15 are neg). You multiplied by 2 and then the signs all became the same. That can't be. You got -2G - 2B = -30. You should catch that error because the if the signs are different they can't become the same and if they are the same they can't become different!

Your last line is also wrong. The first subtraction should be 5G not G. You added to get G!

 

[Ehands1221]

Thanks everyone, all sorted!