hi bobbym mandy here do you now how to do ratio or not?
Yes, I do but you already have a person helping you. If I interfere it might just confuse you. You see everybody has different ways of doing things. When you are learning you should not see too many different ways.
If it ain't broke, fix it until it is.
A number by itself is useful, but it is far more useful to know how accurate or certain that number is.
Hi bobbym mandy here thanks for your help it was helpful
Hi steveb mandy here.3 to 7 ratio scale it up to 100 tins
New total 100
Old total. 10. ( come from 3+7 )
So scaling factor = 100/10 = 10
I get this far then I get stuck?
Can you show me how to do the rest please?
The bit that you have done is correct. I was intending that you would then multiply this scaling factor by the two numbers in the ratio.
So 3 x 10 = 30
and 7 x 10 = 70
So for 100 tins you would have 30 yellow and 70 blue. A quick check would be 30 + 70 = 100 to see that it adds up to 100.
If percentages are needed then they would be 30% yellow and 70% blue.
Can you see what the answer would be for a total of only 50 tins of paint?
hi steveb the answer to 50 tins is
new total 50
old total 10
so scaling factor = 50/10 = 5
so 3 x 5 = 15
and 7 x 5 = 35
so for every 50 tins you would have 15 yellow and 35 blue
am i right?
Yes that is correct. Well done.
now what do you want me to do then?
hi bob bundy mandy here how do you think i am doing then? send message back please?
Right. With that same ratio of 3:7 what would the answer be for a total of 70 tins ?
is it the same as last on or not
The ratio is the same, but the total is different.
i am stuck on this one HELP ME?
Right. The thing that I am calling an old total is the same (3 + 7 = 10). However I have given you a different number for the
new total. The new total is 70. What is the scaling factor in this case ?
so scaling factor = 70/10 = 10
so 3 x 10 = 30
and 7 x 10 = 70
am i right so far ? i am stuck
No. You need to look back at the scaling factor bit. The answer to 70/10 is not 10.
is it 5 am i right?
No that is not correct. I think this is a times tables problem. 5 x 10 = 50 and 10 x 10 = 100 somewhere inbetween these two
guesses lies the answer. I don't want to simply tell you the answer because this is good practice for you.
Do you want to try again?
Last edited by SteveB (2013-03-30 05:08:47)
i will try again and send you my answer at 7.30pm tonight ok see you then buy for now?
Okay see you later.
Hi steveb mandy here i have tried to do that sum again but I can not work it out? Can you help me please?
There are two things here that you need to revise possibly:
(1) Times tables
(2) Division by 10 (and for that matter multiplying by 10)
70 divided by 10 is 7
Each time you have a multiplication in the form: a x b = c
This means that c / a = b
and also c / b = a
(We do need to take care to avoid divisions by zero here, but that is another story)
So here 7 x 10 = 70 70 / 10 = 7 70 / 7 = 10
Hi steveb mandy here i am still a bit confused with these need more practices ok? Send me some to try please?
Right let us try to finish off the question about the 70 tins of paint and how many we need of each colour.
So the scaling factor is 7. Can you finish the question off ?