JAGS Sample paper
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JAGS Sample paper
Question 21 please. The mince pies seem to have slowed my brain down considerably!
http://www.jags.org.uk/userfiles/jagsmv ... -paper.pdf
Jack dances around the Maypole, making one revolution every 5 seconds.
Starting at a point diametrically opposite Jack's starting point, Gill dances anticlockwise making one revolution every 6 seconds.
How many times do they pass each other in the 1st minute?
Thank you.
http://www.jags.org.uk/userfiles/jagsmv ... -paper.pdf
Jack dances around the Maypole, making one revolution every 5 seconds.
Starting at a point diametrically opposite Jack's starting point, Gill dances anticlockwise making one revolution every 6 seconds.
How many times do they pass each other in the 1st minute?
Thank you.
Re: JAGS Sample paper
The original question was on a UKMT challenge with the following choices of answer;
A 11 B 15 C 22 D 30 E 60
Does that help?
A 11 B 15 C 22 D 30 E 60
Does that help?
Re: JAGS Sample paper
Many thanks.
Then I would say 22. Roughly twice every 5 to 6 seconds.
Not sure how I get to 22 exactly without the help of multiple choice.
Then I would say 22. Roughly twice every 5 to 6 seconds.
Not sure how I get to 22 exactly without the help of multiple choice.
Re: JAGS Sample paper
The official solution said:
Jack makes one revolution every five seconds and Jill one revolution every six seconds, on average they turn through angles of 72º and 60º respectively every second. So, as they are travelling in opposite directions, Jill turns, on average, through an angle of 132º per second relative to Jack.
In one minute, therefore, she will turn through an angle of 60 x 132º, that is 22 complete revolutions, relative to Jack. So they will pass each other 22 times in the first minute.
Jack makes one revolution every five seconds and Jill one revolution every six seconds, on average they turn through angles of 72º and 60º respectively every second. So, as they are travelling in opposite directions, Jill turns, on average, through an angle of 132º per second relative to Jack.
In one minute, therefore, she will turn through an angle of 60 x 132º, that is 22 complete revolutions, relative to Jack. So they will pass each other 22 times in the first minute.
Re: JAGS Sample paper
Many thanks for this G55.
Can you please also look at 19?
I can see that the 3 ones on the base are not visible. Additionally I can also see that adjoining faces(not visible) have the following values in order right to left. 5 for the first die, plus total of 7 for the second die, plus a value of the hidden face for the 3rd die. Not sure what the hidden value of the last die could be. I think it could be either a 5 or a 2.
Help appreciated.
Can you please also look at 19?
I can see that the 3 ones on the base are not visible. Additionally I can also see that adjoining faces(not visible) have the following values in order right to left. 5 for the first die, plus total of 7 for the second die, plus a value of the hidden face for the 3rd die. Not sure what the hidden value of the last die could be. I think it could be either a 5 or a 2.
Help appreciated.
Re: JAGS Sample paper
Sorry - went food shopping.
The maypole one I did another way by thinking about how many revs each did in the minute - one does 10 and the other 12. So if we consider one is not moving the other makes 10 +12 = 22 revs.
The dice - as we can see identical faces on each die then I think:
there are three 4s on the back
three 1s underneath
a total of 7 on the 'inside' and rear dice faces of the back two dice
a 5 on the hidden face of the front die
The maypole one I did another way by thinking about how many revs each did in the minute - one does 10 and the other 12. So if we consider one is not moving the other makes 10 +12 = 22 revs.
The dice - as we can see identical faces on each die then I think:
there are three 4s on the back
three 1s underneath
a total of 7 on the 'inside' and rear dice faces of the back two dice
a 5 on the hidden face of the front die
Re: JAGS Sample paper
Perfect, thanks. Managed to hang on while you went to buy food!
On the Maypole question - your explanation is a much better way to explain it than UKMT, bearing in mind the age of the students.
On the Maypole question - your explanation is a much better way to explain it than UKMT, bearing in mind the age of the students.
Re: JAGS Sample paper
The challenge is aimed at Year 7/8 and personally I think it was a bit cheeky to lift it for an exam!
Jack seems to have an interesting life looking at dice and maypole dancing ...
Jack seems to have an interesting life looking at dice and maypole dancing ...
