You lovely people..maths question help please??
Moderators: Section Moderators, Forum Moderators
You lovely people..maths question help please??
question is about various numbers of discs (D), envelopes (E) and squares (S) in balance, they show pictures of scales which are in balance, so ...
A) 2D + 1E = 2S
2D + 3E = 3S
4D + 3E = ?
The top two are in perfect balance. How many squares are needed to balance the bottom set (what is ?).
I MAKE THE ANSWER 5 squares (because 2D + 2D = 4D and 1E + 3E = 4E, therefore 2S + 3S = 5s)
B) [the shapes may not weigh the same as in part (a)]
5D + 1E = 5S
3D + 2E = 4S
6E = ?
The top two scales are in perfect balance. How many squares will be needed to balance the bottom set?
NO IDEA HOW TO WORK THIS OUT!!
...Thank you
A) 2D + 1E = 2S
2D + 3E = 3S
4D + 3E = ?
The top two are in perfect balance. How many squares are needed to balance the bottom set (what is ?).
I MAKE THE ANSWER 5 squares (because 2D + 2D = 4D and 1E + 3E = 4E, therefore 2S + 3S = 5s)
B) [the shapes may not weigh the same as in part (a)]
5D + 1E = 5S
3D + 2E = 4S
6E = ?
The top two scales are in perfect balance. How many squares will be needed to balance the bottom set?
NO IDEA HOW TO WORK THIS OUT!!
...Thank you
Re: You lovely people..maths question help please??
For a), is there an error in your second equation?
For b), your starting point could be 5D + 1E = 5S, so
10D + 2E = 10S
nyr
For b), your starting point could be 5D + 1E = 5S, so
10D + 2E = 10S
nyr
Re: You lovely people..maths question help please??
nyr - isn't it better to elimiate E as we're not interested in it?
Re: You lovely people..maths question help please??
Sorry yes error - part a last equation should say 4D + 4E = ?
None the wiser with part B
None the wiser with part B
Re: You lovely people..maths question help please??
5D + 1E = 5S
3D + 2E = 4S
6E = ?
How could you get the same numbers of Ds in each equation - try this and then get back to me. If I just post the whole solution it won't help you with the next one.
3D + 2E = 4S
6E = ?
How could you get the same numbers of Ds in each equation - try this and then get back to me. If I just post the whole solution it won't help you with the next one.
Re: You lovely people..maths question help please??
I'm getting an answer of 6 squares.. Is that right?
Re: You lovely people..maths question help please??
Can you post or PM me your working ? Also double check the original equations as I seem to be getting fractions
Re: You lovely people..maths question help please??
Multiply the 1st equation by 3: 15D + 3E = 15SAML wrote:B) [the shapes may not weigh the same as in part (a)]
5D + 1E = 5S
3D + 2E = 4S
6E = ?
The top two scales are in perfect balance. How many squares will be needed to balance the bottom set?
Multiply the 2nd equation by 5: 15D + 10E = 20S
Subtract these and the D bit will disappear.
7E=5S
Hmmm. 6E = 5S *6/7
Are you sure you haven't got another typo when you've given us the question?
Re: You lovely people..maths question help please??
DebsB - it's better to give a hint rather than a full solution ... yes I hit the same issue, hence my post.
Re: You lovely people..maths question help please??
arghhh, definitely another typo.
Apologies!
So last line should be 7E ..... (not 6E)
Apologies!
So last line should be 7E ..... (not 6E)