Tutor MathsGuru: Ask me for your burning Maths questions!

[Applelyn1]

Hi, can someone help me on the flwg quest, thank you.


1) Sam and Alvin had 116 marbles at first. After Sam bought another 8 marbles and Alvin gave away 20 of his marbles to his sister, they both had the same number of marbles left. How many marbles did Alvin have at first?

2) There are some pupils in class 4 Dil. 1/3 of them like cycling, 1/4 of them like swimming, 1/6 of them like roller blade and the rest like playing badminton. If 6 more pupils like playing badminton as compared to roller blad, find the total number of pupils in the class.

3) The cost of ToyA is 1/4 of the cost of Toy B and the cost of Toy C is 3/4 of the cost of Toy A. Toy B costs $36 more than Toy A

a) How much does Toy A cost?
b) How much does Toy C cost?

[MathIzzzFun]

Applelyn1:

Hi, can someone help me on the flwg quest, thank you.


1) Sam and Alvin had 116 marbles at first. After Sam bought another 8 marbles and Alvin gave away 20 of his marbles to his sister, they both had the same number of marbles left. How many marbles did Alvin have at first?

Hi

At first, total = 116.
Sam bought 8, total = 116 + 8 = 124
Alvin gave away 20, total = 124 - 20 = 104.

In the end, each has 104 / 2 = 52.

So, number of marbles Alvin had at first = 52 + 20 = 72

cheers.

[MathIzzzFun]

Applelyn1:

Hi, can someone help me on the flwg quest, thank you.


2) There are some pupils in class 4 Dil. 1/3 of them like cycling, 1/4 of them like swimming, 1/6 of them like roller blade and the rest like playing badminton. If 6 more pupils like playing badminton as compared to roller blad, find the total number of pupils in the class.

Hi

Total number of pupils = 12 units

1/3 cycling = 4 units
1/4 swimming = 3 units
1/6 roller blade = 2 units
badminton = 12 units - 4units - 3 units - 2 units = 3 units

so, 3 units - 2 units = 1unit = 6

Total number of pupils in class = 12 x 6 = 72.

cheers.

[MathIzzzFun]

Applelyn1:

Hi, can someone help me on the flwg quest, thank you.


3) The cost of ToyA is 1/4 of the cost of Toy B and the cost of Toy C is 3/4 of the cost of Toy A. Toy B costs $36 more than Toy A

a) How much does Toy A cost?
b) How much does Toy C cost?

Hi

Cost of Toy B = 16 units
Cost of Toy A = 4 units
Cost of Toy C = 3/4 of 4 units = 3 units

Toy B - Toy A = $36
16 units - 4 units = 12 units = $ 36, 1 unit = $ 3

Toy A = 4 units = 4 x $3 = $12
toy C = 3 units = 3 x $3 = $9

cheers.

[Applelyn1]

:thankyou: MathIzzzFun.

[MathIzzzFun]

Applelyn1:

:thankyou: MathIzzzFun.

u r welcome

bon weekend !

cheers.

[rrjan]

Hi, could I kindly get some help with how to explain this qn?


String P is 8 cm longer tan String Q. The total length of String P and String R is 54cm. Find the length of String Q.

Sincere Thanks

[MathIzzzFun]

rrjan:

Hi, could I kindly get some help with how to explain this qn?


String P is 8 cm longer tan String Q. The total length of String P and String R is 54cm. Find the length of String Q.

Sincere Thanks

Pls check the question. There is DEFINITELY information missing or typo error.

cheers.

[rrjan]

Hi MathsIzzzFun,


Thanks for your kind revert. Will ask my son to check with his teacher again. This was adapted from his school's past year exam paper for P3.

My hubby tried to figure it out and came up with this explaination.

Told me to use guess and check method. Taking a presumption that these strings are like strings on a guitar. Since string P is 8 cm longer than string Q, we would also presume that string R is 8 cm shorted than string Q. In order to find string Q, we take 54 /2, and we will get 27. If Q is 27cm, P will be 27cm + 8 cm = 35cm, R = 27cm = 8 cm = 19cm

String P + String R = 35cm + 19cm = 54cm

I kind of understand his expalination, but how to explain it more clearly to my boy?

[MathIzzzFun]

rrjan:

Hi MathsIzzzFun,


Thanks for your kind revert. Will ask my son to check with his teacher again. This was adapted from his school's past year exam paper for P3.

My hubby tried to figure it out and came up with this explaination.

Told me to use guess and check method. Taking a presumption that these strings are like strings on a guitar. Since string P is 8 cm longer than string Q, we would also presume that string R is 8 cm shorted than string Q. In order to find string Q, we take 54 /2, and we will get 27. If Q is 27cm, P will be 27cm + 8 cm = 35cm, R = 27cm = 8 cm = 19cm

String P + String R = 35cm + 19cm = 54cm

I kind of understand his expalination, but how to explain it more clearly to my boy?

Hi

There is definitely missing information in the question. As it is, there are countless number of possible answers. Since the question did not provide any information on the individual strings, we cannot assume that string R is 8 cm shorter than string Q.

P + R = 54 cm
P = Q + 8 cm
So, Q + 8 cm + R = 54 cm
Q + R = 46 cm
So, it is not possible to have only 1 answer for Q, since R is unknown, and Q can take any value that satisfy the statement Q + R = 46 cm.

cheers.