Q&A - P4 Math

[Jamesbond]

http://i49.tinypic.com/mhf3a9.jpg\">


pl help me solve this......

[Jamesbond]

http://i46.tinypic.com/2573bds.jpg\">


The ans for ques (a) is 15 unit shapes...I donno to solve ques (b). Pl help me...............

[MathIzzzFun]

Jamesbond:

http://i46.tinypic.com/2573bds.jpg\">


The ans for ques (a) is 15 unit shapes...I donno to solve ques (b). Pl help me...............

Hi

pattern 1 --> 1 = 1x2 /2
pattern 2 --> 3 = 2x3 /2
pattern 3 --> 6 = 3x4 /2
pattern N = N x (N+1) /2 --> 1/2 x product of pattern number N and the next consecutive number
pattern 5 --> 5x6 /2 = 15

Total = 210
ie 1/2 x product of pattern number N and the next consecutive number = 210
or product of 2 consecutive numbers (N & N+1) = 420
.. use guess and check to find the number N --> the nearest square number = 400 = 20 x 20
20 x 21 = 420
N = 20
Pattern 20 has 210 shapes

cheers.

[Laura02]

MathIzzzFun:

AgonyMum:

Hello, please show me the correct \"formula\" ie the pattern of these 2 questions.Thanks!


1. Figure 1 - 1 cube
Figure 2 - 5 cubes
Figure 3 - 14 cubes

How many cubes are needed to build Figure 10?
(Use patterns, not calculations)

2. Deposit $1 in bank.
On second day, total amount will be $3
On third day, total amount will be $9
On fourth day, total amount will be $27 and so on.
How much money will there be at the end of 10 days?
(Use patterns, not calculations)

Hi

may I know the source of these questions ?

Q1 is a pattern of 3rd order (ie cubic - sum of squares, pattern 1 =1 , pattern 2 = 1x1 + 2x2, pattern 3 = 1x1+2x2+3x3, nth term = n(n+1)(2n+1)/6 ) and as far as I know, P6 students are only required to find pattern or nth term for pattern of 2nd order. For 3rd order pattern, the students are only required to evaluate the nth term based on observation and usually, the nth term is usually less than 10.
So, this question is certainly not a standard P4 question, more likely practice question for maths competition.


Q2. day 1 - 1, day 2 - 1x3 = 3^1, day 3 - 1x3x3 = 3^2, day 10 = 3^9.
again, I think this is beyond P4 maths.

cheers.

Hi!

Could the be more than one answer for Q1?

Say 1 (+4) = 5
5 (+4+5) = 14
14 (+4+5+6) = 29
29 (+4+5+6+7) = 51 ... Ans 283

I'm not a math teacher, so please correct me if I'm wrong.

Which is why maths is fun!

[Thein]

Jamesbond:

http://i49.tinypic.com/mhf3a9.jpg\">


pl help me solve this......

area of intersection=1

area of pebble path=1 x 24 + 1 x 8 - area of intersection=32 - 1

total area of the garden = 24 x 8 = 192

area not covered by path = 192 - 31 =161m2

[MathIzzzFun]

Jamesbond:

http://i49.tinypic.com/mhf3a9.jpg\">


pl help me solve this......

hi

http://i45.tinypic.com/15d03s6.png\">

cheers.

[Jamesbond]

MathIzzzFun:

Jamesbond:

http://i46.tinypic.com/2573bds.jpg\">


The ans for ques (a) is 15 unit shapes...I donno to solve ques (b). Pl help me...............

Hi

pattern 1 --> 1 = 1x2 /2
pattern 2 --> 3 = 2x3 /2
pattern 3 --> 6 = 3x4 /2
pattern N = N x (N+1) /2 --> 1/2 x product of pattern number N and the next consecutive number
pattern 5 --> 5x6 /2 = 15

Total = 210
ie 1/2 x product of pattern number N and the next consecutive number = 210
or product of 2 consecutive numbers (N & N+1) = 420
.. use guess and check to find the number N --> the nearest square number = 400 = 20 x 20
20 x 21 = 420
N = 20
Pattern 20 has 210 shapes

cheers.

:thankyou: :salute: :salute:

[Jamesbond]

Tan participated in a math quiz with 20 questions. For every correct answer, he was awarded 3 points. For every wrong answer, 2 points were deducted. If tan scored 25 points for the quiz, how many questions did tan answer correctly?


Pl help me solve this..... :yikes:

[MathIzzzFun]

Jamesbond:

Tan participated in a math quiz with 20 questions. For every correct answer, he was awarded 3 points. For every wrong answer, 2 points were deducted. If tan scored 25 points for the quiz, how many questions did tan answer correctly?


Pl help me solve this..... :yikes:

Hi

here's a similar question.. using area model..

http://www.flickr.com/photos/62167097@N02/7319052572/in/photostream

cheers.

[kiasuMay11]

MathIzzfun,

Can u explain a little regarding the area model? I cant really get it. Why there are 3 ‘W’?