Primary 2 Maths Question

[JackRabbit]

Hi All

 

Need some help - my kid got this question wrong for a Math Test (Primary 2).

 

I also have no clue what's the right answer.

 

Please help!

 

 

[JackRabbit]

ok.. i found out the correct answer.... but I'll leave this thread open so that you guys can also figure out. I'll post the answer if no one can figure out.

[Jamesc]

I heard kids are pretending to be parents and asking people on the internet

 

for answers to their homework. That way that get their homework done for them free.

 

[Subatoyo]

mon-1

tue-1+1=2

wed-2+2=4

thur-4+3=7

Fri-7+4=11

ans:7

[Jamesc]

The smater kids even pretend to have the correct answers but sill tell people,

 

tell me yours and I will tell you mine.

 

[JackRabbit]

yes..subatoyo got it... well done bro!

[JackRabbit]

The smater kids even pretend to have the correct answers but sill tell people,

 

tell me yours and I will tell you mine.

 

 

 

Good one... ha... psychological warfare at work.

[Subatoyo]

Bro, i am a full time tutor, this is considered elementary and fundamental in current pri sch math. Next yr u will and go hee....

Edited October 26, 2011 by Subatoyo

[JackRabbit]

luckily my time is over.... now only need to worry about real world $$$ calculations...

[Kusje]

mon-1

tue-1+1=2

wed-2+2=4

thur-4+3=7

Fri-7+4=11

ans:7

 

 

Wrong. One circle is 2 eggs.

[Kusje]

yes..subatoyo got it... well done bro!

 

 

You also wrong.

[Freestylers09]

14

 

Wat a tricky qn

[Wasted]

Wrong. One circle is 2 eggs.

 

dun say wrong lah... can say half correct!

 

[Subatoyo]

The question asks how many eggs did she see on the graph being spilled by the milk ?can be interpreted both ways ba . to be precise, shoud be 14

Edited October 26, 2011 by Subatoyo

[Yunfeng]

14 eggs

[VenomMX]

The answer should be 7x2=14

Edited October 26, 2011 by VenomMX

[1fast1]

Just seeing this.

 

Correct answer: 14 eggs. (7 symbols).

 

One of the standard tools to figure out sequences (other than staring at it) is to compute the difference between successive terms.

 

Just working on number of symbols:

 

Mon: 1 -> call that T(1) (for term 1)

 

Tue: 2 -> T(2)

 

Wed: 4 -> T(3)

 

Thurs: ? -> T(4)

 

Fri: 11 -> T(5)

 

Take differences:

 

T(2) - T(1) = 1

 

T(3) - T(2) = 2

 

T(4) - T(3) = ?

 

T(5) - T(4) = ?

 

There are two "common" patterns that start with 1,2...

 

viz. the natural numbers: 1,2,3... and the geometric progression 1,2,4,8...

 

A bit of trial and error here.

 

If you try the latter, you get a value for T(4) [Thursday] of 4+4 = 8 and T(5) [Friday] of 8+16 = 24 which clearly can't be right because you know T(5) is supposed to be 11.

 

So the differences are represented by the natural numbers (the first choice), giving T(4) = 4+3 = 7 and T(5) = 7+4 = 11, which is what we want.

 

(Actually, the Fibonacci series which starts 1,1,2,3,5... from the second term onward is also a contender for the successive differences, but I would expect this to be beyond the scope of a Primary school question. In any case, it doesn't fit either).

 

So T(4) = 7 symbols, or 14 eggs.

 

For the math geeks, this is a simple linear recurrence: T(n) - T(n-1) = n-1, with T(1) = 1

 

Solving it for a closed form will yield T(n) = (n^2 - n + 2)/2 symbols, or (n^2 - n + 2) eggs. From that you can find the answer for Thursday, which is (4^2 - 4 + 2) = (16 - 4 + 2) = 14 eggs.

 

But the last bit of cheeminology is just for fun. And rigour.

[Fran]

My guess is 8 circle which is 16 eggs.