PSLE.
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Simple question. Me is a dragon baby, so I know this question. Only that it added till 97, not 100.Originally posted by LinLing:Oh, and if you can remember, was there any questions like:
1+2+3+4+5+6+7+8+9+10...................+98+99+100=??
The answer is this right..:
100x2-1=199.
Right?
Add 1 to 10 together. What's the answer?
Next add 11 to 20. What's the answer again?
Add 21 to 30. What's the answer?
See a pattern?
The last 2 digits will always be 55 and as the pattern goes on, the hundreds digit increase by one.
So, final answer will be 55+155+255+355+455+555+655+755+855+955 = 5050. -
Wah piang eh....Originally posted by X3Mi5t:Come let me teach u... Me LOVE math...
1+2+3+4+...+98+99+100=?? and 1+3+5+7+9+...+101=?? are all ARITHMETIC SEQUENCES. they have EQUAL differences between the numbers, like 2-1=1, 3-2=1 etc and 3-1=2, 5-3=2 etc.
So, this kind of sequences have a general formula to calculate for the sum one... It's n/2[2a+(n-1)d]. n is the nth term. a is the first term. then d is the common difference between the numbers, like 1 and 2 respectively.
So for the 1st sequence, nth term is the 100th term:
100/2[2*1+(100-1)*1]=5050
The 2nd sequence will be, nth term is 51st term:
51/2[2*1+(51-1)*2]=2601
So that's it!! Easy?
Just apply this formula. The thing will work out. BUT u must be very careful that the sequence has a common difference... as in the differences between the adjacent terms MUST be EQUAL before you apply this formula. Just take note of this pitfall and u'll be fine for this kind of qns.
~cheers~
She PSLE nia, need to show her algebra ma? Although your Maths no doubt is good, but I doubt she understood this whole chunk. A calculator might help her better than your method.
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250 and above is high...you are someone who does well in school all along? just remember to pace yourself. the worst thing that will happen is losing steam around the PSLE because you overstretched yourself in the prelims and midyears..honey, psle is just the start...you have o levels and a levels and perhaps degree and honours to take next time, dont worry too much
Hey do consider NYGH ...
other schools that you could aim for are rvhs, mgs and scgs though each has its own different reputation, depends on your liking
you know what when i was 12 i didn't even know what a forum was -
ehh.. i think it was one of the qns during my year.. lol.. 2000 de..Originally posted by LinLing:Oh, and if you can remember, was there any questions like:
1+2+3+4+5+6+7+8+9+10...................+98+99+100=??
The answer is this right..:
100x2-1=199.
Right?
i think under MCQ.. den i di gum got it correct..
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guys, dun teach him AP or GP, unless it's in their syllabus.
it's meant to be a thinking question for them.... -
aiyo... PSLE get so high for what sia... can get into a decent Secondary can le lah. In Secondary life you might get a few asking your result nia. That happened only during the 1st period of sec 1. After that, nobody would even care for your ... what ? .. PSLE ? ... come'on man.
When you reached tertiary level. Ha.... you would be thinking of throwing all that you have achieved during your primary school years man ... haha... try your best can le.... dun stress for PSLE ... dun worth...
All the best though... -
i hardly study and got aggregate of 174...if u dont wanna end up in NA,work hard
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come on la, how the heck do u expect a 12 yr old to do power of 5 now...Originally posted by X3Mi5t:Oh... and by the way, if u're wondering whether there's any other kind of sequences, there is. I know of another one that is called GEOMETRIC sequence.
For this kind of sequence, the ratio between the terms must be the same. Ratio as in, the 2nd term divide by the 1st term = 3rd term divide by the 2nd term. This kind of sequence have a special formula: [a(1-r^n)]/(1-r). a, as usual, is the starting term. n is the nth term. r is the common ratio.
Let me give u an example:
1+3+9+27+...+81=??
First, look at the common ratio: 3/1=3, 9/3=3, 27/9=3. Hence, u can see that the common ratio for this sequence is 3. And the ratio is constant throughout, so u can safely use the formula. The nth term is the 5th term.
Therefore, [1(1-3^5)]/(1-3)=121.
ok, just like that. that's all.... just remember: equal ratio. -
dun be surprised.. i believe there are many Primary 6 students tt are capable of solving tt power of @#$%^ thingy
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kan chime!Originally posted by ndmmxiaomayi:Simple question. Me is a dragon baby, so I know this question. Only that it added till 97, not 100.
Add 1 to 10 together. What's the answer?
Next add 11 to 20. What's the answer again?
Add 21 to 30. What's the answer?
See a pattern?
The last 2 digits will always be 55 and as the pattern goes on, the hundreds digit increase by one.
So, final answer will be 55+155+255+355+455+555+655+755+855+955 = 5050.
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mix school is good
too bad im not in one -
so fast chionging for psle
dun overstress ureself
relax first -
i got 211 haha
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study smart not hardOriginally posted by LinLing:VERY HARD. -
please. 250 is a shitty score if you want to consider nygh. i think you should aim for RGS. get at least 260. that would be an A* for everything.Originally posted by jayellefull:250 and above is high...you are someone who does well in school all along? just remember to pace yourself. the worst thing that will happen is losing steam around the PSLE because you overstretched yourself in the prelims and midyears..honey, psle is just the start...you have o levels and a levels and perhaps degree and honours to take next time, dont worry too much
Hey do consider NYGH ...
other schools that you could aim for are rvhs, mgs and scgs though each has its own different reputation, depends on your liking
you know what when i was 12 i didn't even know what a forum was -
don't log on here too often, serious. revise more
you are on the track already, at least you don't type like jessie** -
wtf? that looks like permutations.Originally posted by X3Mi5t:Come let me teach u... Me LOVE math...
1+2+3+4+...+98+99+100=?? and 1+3+5+7+9+...+101=?? are all ARITHMETIC SEQUENCES. they have EQUAL differences between the numbers, like 2-1=1, 3-2=1 etc and 3-1=2, 5-3=2 etc.
So, this kind of sequences have a general formula to calculate for the sum one... It's n/2[2a+(n-1)d]. n is the nth term. a is the first term. then d is the common difference between the numbers, like 1 and 2 respectively.
So for the 1st sequence, nth term is the 100th term:
100/2[2*1+(100-1)*1]=5050
The 2nd sequence will be, nth term is 51st term:
51/2[2*1+(51-1)*2]=2601
So that's it!! Easy?
Just apply this formula. The thing will work out. BUT u must be very careful that the sequence has a common difference... as in the differences between the adjacent terms MUST be EQUAL before you apply this formula. Just take note of this pitfall and u'll be fine for this kind of qns.
~cheers~
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i got 260+ ...hehe...jus don panic...coz thats wad i felt on de day before my 1st written exam, eng paper 1 and 2...gt high fever on de next day but i still choing for exam...for me..de PSLE is easier than my skool exams..comes as a bit of a surprise to me..many peps thought national exams are out to kill you off...actually no...
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Err... What's this language? And what it means?Originally posted by 798:kan chime!
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PSLE is easy. To do well in chinese and science just memorize everything. For math practice math problems. The good way to improve your english is to read more books or go for english tuition at a good tuition centre (e.g the learning lab).
I didnt study hard for my PSLE and i already got 241. Not very good lar hahaha but it isnt totally bad. -
Originally posted by LinLing:
As I want to get ready for my PSLE in advance, can the older ones please tell me some tips and some good revision books to use? How did you study and maybe suggest some good sec schools?
I really need it!! (My brother said he don't know. =P)
And if it is possible, ALL THE INFORMATION ABOUT PSLE.
sia la... u so young ah?? -
just listen in class confirm can do well.. and do lots of practice (past year paper etc). PSLE simple la dun worry teachers always like to scare u by saying it's damn hard and stuff. you should use your prelim marks to see where u stand (normally prelim would be harder). Then from there u can improve lor.
btw
1+2+3+4..+100
= 100x101 /2
easy :p
and if 1+3+5..+79+81.. dun ki siao and do power of 5
= 1+3+5..+77+79 (+81)
first u take 79+1 (first and last number) =80 and 77+3 = 80 also.. see pattern?
then to know number of numbers.. take (79-1)/2 + 1 = 40 numbers. which means 20 groups, and u know each group = 80
so answer is 20 x 80 + 81. which is 1681. -
youngest forumer??
i thought the thread's another joke when i saw the title.... until i read it's cotents -
FRANKLY speaking from experience, PSLE is much easier than your school's exams, so is O LEVELS.Obviously because they want more people to pass, as simple as that.
I also feel that they should teach some algebra to solve story solving problems.I could not understand a sh*t when they tried to teach me to use "models" to solve the question but could understand it better when algebra was used. -
Aiyo.Originally posted by ^tamago^:and come, let me teach you, "I before E, except after C."
Ad for SMU can have such a typo?