Tutor MathsGuru: Ask me for your burning Maths questions!

[jieheng]

CJM:

Mr Goh is 3 times as old as his daughter who is 12 years old. What will be their total age in 13 year's time?

Daughter = 12 yrs old

Father = 3 * 12 = 36 yrs old

Their total age in 13 year's time = 12 + 36 + 13*2 = 74 (Ans)

[jieheng]

Daddy:

Hi,


Need help on the question.

Jason, Kelvin and Lily had a total of 161 stamps at first. Jason gave away 1/5 of his stamp. Kelvin received 34 more stamps. Lily bought some more stamps and hence tripled her original number of stamps. Then, the ratio of the number of stamps Jason, Kelvin and Lily had was 2:3:6. How many stamps did Kelvin have at first.


Thanks.
Daddy

J 2u
K 3u
L 6u

J 4u (4/5 after gave away 1/5)
K 6u
L 12u

At First
J 5u (4u+1u)
K 6u-34
L 4u (12u/3)

total= 5u + (6u-34) + 4u -----> 161

15u -34 -----> 161

15u -----> 195

1u -----> 13

Number of stamps that Kelvin had at first = 6u - 34 = 6*13 - 34 = 78 - 34 = 44 (Ans)

[YumYum]

hi,


Can anyone pls assist with the foll Qns:

1. I have 190 Singapore and Malaysia stamps altogether, of which 147 are floral stamps. 3/4 of my Singapore stamps are floral while 5/6 of my Malaysia stamps are floral. How many Singapore stamps do I have?

2. The total number of pupils in the two classes 6A and 6B is 84. 5/8 of 6A pupils and 3/4 of 6B pupils add up to 58. Fing the number of pupils in 6B.

3. Allan had 60 more stamps than Becky. They each gave some of their stamps to their friends. The number of stamps Becky gave away was 2/5 of the number of stamps Allan had at first; the number of stamps Allan gave away was 2/3 of the number of stamps Becky had at first; Both had an equal number of stamps left. How many stamps did Allan have at first?

many thanks. :lol:

[Daddy]

Hi jieheng,


How did you get
[quote]Jason, Kelvin and Lily had a total of 161 stamps at first. Jason gave away 1/5 of his stamp. Kelvin received 34 more stamps. Lily bought some more stamps and hence tripled her original number of stamps. Then, the ratio of the number of stamps Jason, Kelvin and Lily had was 2:3:6. How many stamps did Kelvin have at first. [/quote][quote]J 2u
K 3u
L 6u

J 4u (4/5 after gave away 1/5)
K 6u
L 12u

At First
J 5u (4u+1u)
K 6u-34
L 4u (12u/3)

total= 5u + (6u-34) + 4u -----> 161
15u -34 -----> 161
15u -----> 195
1u -----> 13
Number of stamps that Kelvin had at first = 6u - 34 = 6*13 - 34 = 78 - 34 = 44 (Ans)[/quote]How did you get Kelvin 6u & Lily 4u? Sorry, I did not understand?

[jieheng]

Daddy:

Hi jieheng,


How did you get
[quote]Jason, Kelvin and Lily had a total of 161 stamps at first. Jason gave away 1/5 of his stamp. Kelvin received 34 more stamps. Lily bought some more stamps and hence tripled her original number of stamps. Then, the ratio of the number of stamps Jason, Kelvin and Lily had was 2:3:6. How many stamps did Kelvin have at first.

[quote]J 2u
K 3u
L 6u

J 4u (4/5 after gave away 1/5)
K 6u
L 12u

At First
J 5u (4u+1u)
K 6u-34
L 4u (12u/3)

total= 5u + (6u-34) + 4u -----> 161
15u -34 -----> 161
15u -----> 195
1u -----> 13
Number of stamps that Kelvin had at first = 6u - 34 = 6*13 - 34 = 78 - 34 = 44 (Ans)[/quote]How did you get Kelvin 6u & Lily 4u? Sorry, I did not understand?[/quote]Jason left 4/5 after he gave 1/5 away ,

we need to make the units of Jason to 4u

Ratio of J : K : L = 2u : 3u : 6u

(2u*2 : 3u*2 : 6u*2)

change the ratio of J : K : L = 4u : 6u : 12u (2u*2 : 3u*2 : 6u*2)

[jieheng]

YumYum:

hi,


Can anyone pls assist with the foll Qns:

1. I have 190 Singapore and Malaysia stamps altogether, of which 147 are floral stamps. 3/4 of my Singapore stamps are floral while 5/6 of my Malaysia stamps are floral. How many Singapore stamps do I have?

Note : There is no direct relationship between Singapore stamps and Malaysia stamps

S [--][--][--][--]

M {---}{---}{---}{---}{---}{---}

[--] and {---} are floral stamps

[--] and {---} are non-floral stamps

[--] = [--] and {---} = {---}

given total stamps = 190 , total floral stamps = 147

total non-floral stamps = 190 - 147 = 43

[--] + {---} = 43 (1 set)

[--][--][--][--] + {---}{---}{---}{---} = 43 * 4 = 172 (4 sets)

total stamps = 190

[--][--][--][--] + {---}{---}{---}{---}{---}{---} = 190

[--][--][--][--] + {---}{---}{---}{---} + {---}{---} = 190

172 + {---}{---} = 190

{---}{---} =190 - 172 = 18

{---} = 18/2 = 9

{---}{---}{---}{---}{---}{---} = 9*6 = 54

[--][--][--][--] + {---}{---}{---}{---}{---}{---} = 190

[--][--][--][--] + 54 = 190

[--][--][--][--] = 190 -54 = 136

total number of Singapore stamps = 136 (Ans)

[jieheng]

YumYum:

hi,


Can anyone pls assist with the foll Qns:

2. The total number of pupils in the two classes 6A and 6B is 84. 5/8 of 6A pupils and 3/4 of 6B pupils add up to 58. Fing the number of pupils in 6B.

Note : There is no direct relationship between pupils in 6A and pupils in 6B

6A [--][--][--][--][--][--][--][--] (total 8*[--])

6B {---}{---}{---}{---} (total 4*{---})

[--] = [--] and {---} = {---}

given [--][--][--][--][--] + {---}{---}{---} = 58

[--][--][--] + {---} = 84 - 58 = 26 (1 set)

12*[--] + 4*{---} = 26*4 = 104 (4 sets)

8*[--] + 4*[--] + 4*{---} = 104

4*[--] + 84 = 104

4*[--] = 104 - 84 = 20

8*[--] = 20*2 = 40

number of pupils in 6A = 40

number of pupils in 6B = 84 - 40 = 44 (Ans)

[jieheng]

YumYum:

hi,


Can anyone pls assist with the foll Qns:

3. Allan had 60 more stamps than Becky. They each gave some of their stamps to their friends. The number of stamps Becky gave away was 2/5 of the number of stamps Allan had at first; the number of stamps Allan gave away was 2/3 of the number of stamps Becky had at first; Both had an equal number of stamps left. How many stamps did Allan have at first?

A [----15u------][--60--]

B [----15u------]

reason for using 15u because it is the common multiples of 3 and 5

2/5 of A is 6u+24

2/3 of B is 10u


A [----15u------][--60--] - 10u

B [----15u------] - (6u+24)

15u + 60 - 10u -----> 15u - (6u+24)

5u + 60 -----> 9u - 24

4u -----> 84

1u -----> 21

15u -----> 21*15 = 315

number of stamps Allan had at first = 15u + 60 = 315 + 60 = 375 (Ans)

[YumYum]

jieheng:

YumYum:

hi,


Can anyone pls assist with the foll Qns:

3. Allan had 60 more stamps than Becky. They each gave some of their stamps to their friends. The number of stamps Becky gave away was 2/5 of the number of stamps Allan had at first; the number of stamps Allan gave away was 2/3 of the number of stamps Becky had at first; Both had an equal number of stamps left. How many stamps did Allan have at first?

A [----15u------][--60--]

B [----15u------]

reason for using 15u because it is the common multiples of 3 and 5

2/5 of A is 6u+24

2/3 of B is 10u


A [----15u------][--60--] - 10u

B [----15u------] - (6u+24)

15u + 60 - 10u -----> 15u - (6u+24)

5u + 60 -----> 9u - 24

4u -----> 84

1u -----> 21

15u -----> 21*15 = 315

number of stamps Allan had at first = 15u + 60 = 315 + 60 = 375 (Ans)

Hi JieHeng,

Thank you for the detailed explanations. They certainly help.

[MUMMYOF3]

Hi,


Can someone assist me with the following P5 question : -

Alan, Benny, Clement and Danny has 105 marbles. Alan lost 3 marbles and Danny lost 1/2 of what he had. Benny’s sister gave Benny another 6 marbles. Clement’s aunt rewarded Clement by doubling what he had originally. In the end, the 4 boys had an equal number of marbles. How many more marbles than Danny did Alan at first ?