Hi,


Can you pm me the contact as well?

Many thanks

Noted. Thank you.

yeonee:

chloecube:

Q5)


Assuming all are goats,
65 x 4 = 260
260 – 196 = 64
Difference numbers of legs between duck and goat = 4-2 = 2
64/2 =32 ducks
65 – 32 = 33 goats

Check : 32 ducks x 2 legs = 64
33 goats x 4 legs = 132
64 + 132 = 196 legs

Q6)
Assuming all are cows,
75 x 4 = 300
300-220=80
Difference numbers of legs = 4-2 = 2
80/2=40ducks
75-40=35 cows

Check : 40 ducks x 2 legs =80
35 cows x 4 legs = 140
140+80=220 legs

Q7)
Assuming she answered all correctly:
20 x 5 = 100
100 – 79 = 21
Differences = 5+2 = 7
21 / 7 = 3 wrong answers
20 – 3 =17 correct answers

Check: 17 x 5 = 85
3 x 2 = 6
85 -6=79

Q8)

Assuming all coins are 50cents
38 x 50cents = $19
19 – 13.60 = 5.40
Differences = 50-20= 30cents
5.4/ 0.3 = 18 20cents
38 – 18 = 20 50cents
Ratio : 18 : 20
9: 10

i am stuck for Q1,4,9,
Tianshu, can help? thks!

Hi,

I don't understand why the answer to question 7 is 17. If she answered 17 correct questions and 3 wrong questions, isn't her marks 94 [(17x5) + (3x2)]?

Sorry, typo error. Should be 3x3.

chloecube:

Q5)


Assuming all are goats,
65 x 4 = 260
260 – 196 = 64
Difference numbers of legs between duck and goat = 4-2 = 2
64/2 =32 ducks
65 – 32 = 33 goats

Check : 32 ducks x 2 legs = 64
33 goats x 4 legs = 132
64 + 132 = 196 legs

Q6)
Assuming all are cows,
75 x 4 = 300
300-220=80
Difference numbers of legs = 4-2 = 2
80/2=40ducks
75-40=35 cows

Check : 40 ducks x 2 legs =80
35 cows x 4 legs = 140
140+80=220 legs

Q7)
Assuming she answered all correctly:
20 x 5 = 100
100 – 79 = 21
Differences = 5+2 = 7
21 / 7 = 3 wrong answers
20 – 3 =17 correct answers

Check: 17 x 5 = 85
3 x 2 = 6
85 -6=79

Q8)

Assuming all coins are 50cents
38 x 50cents = $19
19 – 13.60 = 5.40
Differences = 50-20= 30cents
5.4/ 0.3 = 18 20cents
38 – 18 = 20 50cents
Ratio : 18 : 20
9: 10

i am stuck for Q1,4,9,
Tianshu, can help? thks!

Hi,

I don't understand why the answer to question 7 is 17. If she answered 17 correct questions and 3 wrong questions, isn't her marks 94 [(17x5) + (3x2)]?

ADoc:

yeonee:

[quote=\"Dharma\"]
144 = ( 2 x 2 x 2 ) x ( 2 x 3 x 3 ) = 8 x 18
Ben’s age now = 18
Ben’s younger brother’s age = 8
Ben’s age in 20 years’ time = 18 + 20 = 38

Sorry. Could u explain why (2x2x2) x (2x3x3)?

Hi Veonee! Dharma was using a more \"advanced\" concept of factorisation (versus guess & check) in order to find the two numbers that give 26 and 144 when added and multiplied together.

If you were to (prime) factorise 144 into its basic components, you will get
2 x 2 x 2 x 2 x 3 x 3. (start by dividing with 2, proceed to the next (prime) number, 3, when the quotient is no longer divisible by 2)

An alternative (and perhaps more intuitive) for primary students would be to write down all the factors of 144:
1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 36, 48, 72, 144
and find two numbers that add and multiply to give 26 and 144.[/quote]
OIC. Thank you very much.

Dharma:

yeonee:

Need Help!


The sum of Ben's age and his younger brother's age is 26. The product of their ages is 144.
What is Ben's age in 20 years' time?

144 = ( 2 x 2 x 2 ) x ( 2 x 3 x 3 ) = 8 x 18
Ben’s age now = 18
Ben’s younger brother’s age = 8
Ben’s age in 20 years’ time = 18 + 20 = 38

Sorry. Could u explain why (2x2x2) x (2x3x3)?

Need Help!


The sum of Ben’s age and his younger brother’s age is 26. The product of their ages is 144.
What is Ben’s age in 20 years’ time?

tianzhu:

yeonee:

Hi, if there were 26 cookies, how can it be shared equally among 9 children? I thought it's a guess and check question. My answer is 18 cos' I thought each child will get 2 cookies if shared among 9 to share among 13 children, we need 8 more cookies. Correct me if I'm wrong.

Hi

I left the answer as 26 per children earlier.

sorry, should be 18*13 = 234 or 26*9 = 234

The answer is 234 cookies

Best wishes

Thank you.

tianzhu:

9*8 = 72

72/4 = 18

18 + 9 = 26

There were 26 cookies in the packet.

Best wishes

Hi, if there were 26 cookies, how can it be shared equally among 9 children? I thought it's a guess and check question. My answer is 18 cos' I thought each child will get 2 cookies if shared among 9 to share among 13 children, we need 8 more cookies. Correct me if I'm wrong.

Hi, another question:-


A packet of cookies was shared equally among 9 children. If 4 more children joined in, each child would get 8 fewer cookies. How many cookies were there in the packet?