can somebody please explain these!
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can somebody please explain these!
Over the weekend my dd attempted her first maths nfer paper, on which she scored 78%, which i thought wasn't too bad for her first try.Could anybody explain the best way to tackle the ones she got wrong, many thanks.
hanif will be x years old 7 years from now
how old was he 7 years ago
craig is arranging plates of food for a party.
he has 3 types of sandwich,2 types of cake,and 4 types of biscuit.
which shows the number of possible combinations of sandwich,cake and biscuit on a plate
(3x2)+(3x4)
3x2x4
(3x4)+(2x4)
3+2+4
(2x3)+(2x4)
and last but not least(sorry)
question 41, which shows a flat shape with the shaded corners cut out and you are asked to find the capacity once it is folded into a small open box.The dimensions are 8cmx6cmx6cm.
the answer they give is 16cm3
truly grateful and exhausted lol
hanif will be x years old 7 years from now
how old was he 7 years ago
craig is arranging plates of food for a party.
he has 3 types of sandwich,2 types of cake,and 4 types of biscuit.
which shows the number of possible combinations of sandwich,cake and biscuit on a plate
(3x2)+(3x4)
3x2x4
(3x4)+(2x4)
3+2+4
(2x3)+(2x4)
and last but not least(sorry)
question 41, which shows a flat shape with the shaded corners cut out and you are asked to find the capacity once it is folded into a small open box.The dimensions are 8cmx6cmx6cm.
the answer they give is 16cm3
truly grateful and exhausted lol
Hi 0505
I can answer the 1st 2 but would need a bit more information on the flat shape to answer No. 3.
Question 1
If Hanif will be x years old in 7 years time, that means he will be (x-7) today.
It follows therfore that 7 years ago he was (x-14) yeasr old.
Question 2
I remember this with my son a few years ago - he was confused as the question was ambiguous. I believe they intend the children to deduce that the plate can contain anything from 1 item (of any description) to a plate containing sandwiches, cakes and biscuit (of any type).
In this situation the number of combinations is (b) 3 x 2 x 4
I would worry about the last question, I don't think it's well written. My son is very good a maths (in year 8 at grammar now) and he struggled with this type of question - it's often the good mathematicians that struggle with this type of badly written question.
Hope this helps
I can answer the 1st 2 but would need a bit more information on the flat shape to answer No. 3.
Question 1
If Hanif will be x years old in 7 years time, that means he will be (x-7) today.
It follows therfore that 7 years ago he was (x-14) yeasr old.
Question 2
I remember this with my son a few years ago - he was confused as the question was ambiguous. I believe they intend the children to deduce that the plate can contain anything from 1 item (of any description) to a plate containing sandwiches, cakes and biscuit (of any type).
In this situation the number of combinations is (b) 3 x 2 x 4
I would worry about the last question, I don't think it's well written. My son is very good a maths (in year 8 at grammar now) and he struggled with this type of question - it's often the good mathematicians that struggle with this type of badly written question.
Hope this helps
Hi Mike
Sorry to be a pain but can you explain the 'Hanif's age' answer and how you work it out. I cannot see why the x means 7 why can it not mean any other number.
These were never my thing at school and I struggled with them two years ago when I was tutoring my son and am worried as I will be tutoring my daughter soon. If I don't get them how will I explain them to my little girl?
Help
Mel
Sorry to be a pain but can you explain the 'Hanif's age' answer and how you work it out. I cannot see why the x means 7 why can it not mean any other number.
These were never my thing at school and I struggled with them two years ago when I was tutoring my son and am worried as I will be tutoring my daughter soon. If I don't get them how will I explain them to my little girl?
Help
Mel
x does not mean 7. x represents any number. Take an example
If Hanif will be 30 in 7 years time, then he is 23 now, and was 16, 7 years ago. In other words, 30-7-7 or 30-14.
If Hanif will be 52 in 7 years time, then he is 45 now, and was 38, 7 years ago. In other words, 52-7-7 or 52 -14.
The x is taking the place of the 30 or 52, and actually can't equal less than 14 because it is impossible to have a negative age.
The point of using x instead of 30 or 52 or any other age greater than 14, is that it gives you an equation for all cases within the limits. This is the whole point of algebra, to give you a one-liner that sums up what would otherwise take several sentences to explain.
If Hanif will be 30 in 7 years time, then he is 23 now, and was 16, 7 years ago. In other words, 30-7-7 or 30-14.
If Hanif will be 52 in 7 years time, then he is 45 now, and was 38, 7 years ago. In other words, 52-7-7 or 52 -14.
The x is taking the place of the 30 or 52, and actually can't equal less than 14 because it is impossible to have a negative age.
The point of using x instead of 30 or 52 or any other age greater than 14, is that it gives you an equation for all cases within the limits. This is the whole point of algebra, to give you a one-liner that sums up what would otherwise take several sentences to explain.