Q&A - P4 Math

[atutor2001]

ozora:

need help:

1)2 similar shirts cost $26 more than 3 pairs of shoes. If their total cost is $158. find the cost of 1 shirt.

2) shop A had 164 more customers than shop B.
after 1/4 of the customers in shop A went to shop B. there were 48 more customers in shop B than shop A.
How many customers were there in shop A and shop B now?

Algebra is the easier way. Anyway, if you wish to solve it using logical thinking, a possible way is as follows :

A is 164 more than B.
To make A and B equal, 164/2 = 82 must move from A to B
To make B more than A by 48, another 48/2 = 24 must move from A to B
(common mistake is in forgetting to divide by 2)

So a total of 82 + 24 = 106 must move from A to B so that B will be 48 more than A.

This 106 is 1/4 of the original number in A.

So the original number in A is 4 quarters, that is 106 x 4 = 424
So the original number in B is 424 - 164 = 260

The number in A now is 424 - 106 = 318
or
The number in A now is 3/4 of the original 3/4 x 424 = 318

The number in B now is 260 + 106 = 366

Personally I don't recommended this way to solve. Too much thinking needed.

[MathIzzzFun]

ozora:

tianzhu:

[quote=\"ozora\"]need help:

1)2 similar shirts cost $26 more than 3 pairs of shoes. If their total cost is $158. find the cost of 1 shirt.

2) shop A had 164 more customers than shop B.
after 1/4 of the customers in shop A went to shop B. there were 48 more customers in shop B than shop A.
How many customers were there in shop A and shop B now?

Hi

Good Morning.

2 shirts ------- 3 shoes + 26

3 shoes + 26 + 3 shoes ----- 158

6 shoes ------- 132
3 shoes -------- 66

2 shirts ------- 66 + 26 -------- 92

1 shirt ------- 46

At first
Shop A ------- 4 units + 164
Shop B ------- 4 units

In the end
Shop A ------- 3 units + 123
Shop B ------- 5 units + 41

3 units + 123 + 48 ------- 5 units + 41
1 unit ------ 65

Shop A ------- 3*65 + 123 ------- 318
Shop B ------- 5*65 + 41 ------- 366

Best wishes

thanks
. for question no 2: i can't solve it unless using algebra
any possible methods? I got the answer684[/quote]Hi
using MD

http://i40.tinypic.com/2nqh15f.png\">


cheers.

[ozora]

MathIzzzFun:

ozora:

[quote=\"tianzhu\"]
Hi
using MD

http://i40.tinypic.com/2nqh15f.png\">


cheers.

[/quote]thanks.
may I ask 164 is divided into 4 parts based on the denominator of 1/4, right?

[MathIzzzFun]

ozora:

MathIzzzFun:

Hi
using MD

http://i40.tinypic.com/2nqh15f.png\">


cheers.

thanks.
may I ask 164 is divided into 4 parts based on the denominator of 1/4, right?

yes

cheers.

[chloecube]

What is the sum of the first 30 even numbers?

2+4+6+8…+56+58+60=

I know there shld a a formula to solve such question.
Can anyone help?

[tianzhu]

chloecube:

What is the sum of the first 30 even numbers?

2+4+6+8......+56+58+60=

I know there shld a a formula to solve such question.
Can anyone help?

Hi

2+4+6+8......+56+58+60 = 2(1+2+3+ --------- 30)

I think students are familiar with calculating the sum of consecutive numbers.

(1+2+3+ --------- 30) = 465

2*465 = 930

Another way to look at it, there are 15 pairs of 62.

2 + 60 = 62
4 + 58 = 62

15*62 = 930

Best wishes

[Nebbermind]

Another similar way is…Because (2 + 58), (4 + 56)… makes a nice number such as 60, there will be 14 such pairs in this series, with 30 & 60 being the odd ones without a partner.


Therefore (14*60) + 30 + 60.

The reason for choosing this is because its easier to work with numbers which r multiples of 10. May not work for all qns though.

[Champion]

Hi, need help with the following questions; :thankyou:


1) The sum of 3 numbers is 350. The difference between the first number and the second number is 25. The difference between the second and the third number is 36. What is the first number if the first number is the smallest and the third number id the largest?

2) Mrs. Kee baked 3 cakes and shared them equally among her 4 children. How much cake did 3 of her children received? Express your answer in fraction in its simplest form.

[PiggyLalala]

Champion:

Hi, need help with the following questions; :thankyou:


1) The sum of 3 numbers is 350. The difference between the first number and the second number is 25. The difference between the second and the third number is 36. What is the first number if the first number is the smallest and the third number id the largest?

2) Mrs. Kee baked 3 cakes and shared them equally among her 4 children. How much cake did 3 of her children received? Express your answer in fraction in its simplest form.

First =second- 25
Third = second +36
First + second + third = 350
Second -25 +second +second + 36 = 350
3x second =350 -11
3xsecond = 339
Second = 339/3= 113
First = 113-25 = 88
Third =113 +36= 149

Second question: 3/4x3=9/4 =2 1/4

[24hr-mum]

how to do this and how to draw the model?


cameron and niki had a total of 136 guppies at first.
After cameron had bought another 14 guppies and niki gave away 40 guppies, both
have the same number of guppies left. how many guppies did cameron have at first?

i cant understand why it is not 136-14-14-40 for the first step.