Tutor MathsGuru: Ask me for your burning Maths questions!

[jieheng]

mummyoftwo:

Hi need help on these 3 Fractions problem sum, can someone help?


3. Thed spent 3/8 of his money on books. Tony spent 1/2 of his money on magazine and had $15 left. If Tony Tony had half of what Thed had in the beginning, how much did Thed spend on his books?

Thed [][][][][][][][]

Tony [][][][]

2u -----> 15
1u -----> 7.5

The amount of money that Thed spent on his books = 3u = 3 * 7.5 = $22.50 (Ans)

[wahwah]

Hi,

Need help with math again. Many thanks in advance.

1. Annie wrote her mother’s age followed by her own age to form a 4-digit number. She used the difference between their ages to subtract from the 4-digit number. Then Annie obtained the number 4489. What was Annie’s age?

2. Wayne had five more 50cents coins than 20cents coins. After he used eight 50cents coins, the value of 50cents coins is $1.50 more than the value of 20cents coins. How many coins did he have at first?

3. A box and 4 similiar files weighed 7.6kg. Tom added 2 more such files and 5 identical books inot the box and the total weight became 14.2 kg. Each file weighed 3 times as much as a book. What is the weight of the box?

4. Mr Tan bought three times as many badges as toy cars ad spent $144 in total. He spent $84 more on toy cars than on badges. given that a toy car costs $10.40 more than a badge, what is the cost of a badge?

[jieheng]

wahwah:

Hi,

Need help with math again. Many thanks in advance.

2. Wayne had five more 50cents coins than 20cents coins. After he used eight 50cents coins, the value of 50cents coins is $1.50 more than the value of 20cents coins. How many coins did he have at first?

50cents [------][ 3][5]
20cents [-----][3]

value of [3] = 3 * 0.2 = $0.60

the difference in value between [------] and [-----] = 1.5 + 0.6 = 2.1

the difference in value of one coin between 50 cents and 20 cents = $0.30

number of coins in [------] = 2.1 / 0.3 = 7

Total number of coins he had at first =( 7 + 3 ) * 2 + 5 = 25 (Ans)

[jieheng]

wahwah:

Hi,

Need help with math again. Many thanks in advance.

3. A box and 4 similiar files weighed 7.6kg. Tom added 2 more such files and 5 identical books inot the box and the total weight became 14.2 kg. Each file weighed 3 times as much as a book. What is the weight of the box?

Box + 4 Files = 7.6

Box + 4 Files + 2 Files + 5 Books = 14.2

7.6 + 2 Files + 5 Books = 14.2

2 Files + 5 Books = 14.2 - 7.6 = 6.6

6 Book + 5 Books = 6.6

1 Book = 6.6 / 11 = 0.6

1 File = 3 Books = 3 * 0.6 = 1.8

Box + 4 Files = 7.6

Box + 4 * 1.8 = 7.6

Box = 7.6 - 7.2 = 0.4

The weight of the box = 0.4 kg (Ans)

[jieheng]

wahwah:

Hi,

Need help with math again. Many thanks in advance.

4. Mr Tan bought three times as many badges as toy cars ad spent $144 in total. He spent $84 more on toy cars than on badges. given that a toy car costs $10.40 more than a badge, what is the cost of a badge?

B [-----][-----][-----]

C [-----]

cost of the badges = (144 - 84) / 2 = 30

cost of the 1 unit of badges = 30 / 3 =10

cost of the toy cars = 30 + 84 = 114

the difference between 1 unit of the cost of the toy cars and 1 unit of the cost of the badges = 114 - 10 = 104

Given the difference between 1 piece of the cost of the toy cars and 1 piece of the cost of the badges = 10.4

the number of the badges in 1 unit = 104 /10.4 = 10

The cost of a badge = $10 / 10 = $1 (Ans)

[jieheng]

wahwah:

Hi,

Need help with math again. Many thanks in advance.

1. Annie wrote her mother's age followed by her own age to form a 4-digit number. She used the difference between their ages to subtract from the 4-digit number. Then Annie obtained the number 4489. What was Annie's age?

the age of Annie is [A1][A2]

the age of her monther is [M1][M2]

the 4-digit number is [M1][M2][A1][A2]

[M1][M2][A1][A2] - ( [M1][M2] - [A1][A2] ) = [M1][M2][A1][A2] + [A1][A2] - [M1][M2]

[M1][M2][A1][A2]
.......... + [A1][A2 ]
........... - [M1][M2]
***************
4.......4......8......9

(...........) is for alignment purpose

From the above , [M1] = 4

[M1] > [A1] as the mother's age is bigger than Annie's age

[A1] is either 1 , 2 or 3

From the ten-digits

[A1] + [A1] - [M1] = 8

[A1] + [A1] = 8 + [M1] = 8 + 4 = 12

so [A1] = 1 as ( [A1] + [A1] = 2)

[M2] has to be 5

From the one-digits

[A2] + [A2] - [M2] = 9

[A2] + [A2] = 9 + [M2] = 9 + 5 = 14

so [A2] = 7 as ( [A2] + [A2] = 14)

the 4-digit number is 4517

Check : 4517 - (45 - 17) = 4517 - 28 = 4489

Annie's age was = 17 (Ans)

Hope you understand my explanation .

[Vanilla Cake]

Pls help to solve the following Maths sums:


Question
(19/20+1919/2020+191919/202020+.......1919...19/2020...20)x20/2011=?
Note: 1919...19/2020...20 means 2011 \"19\"/2011 \"20\"
(4 marks)

Question
(100xa+10xb+c)x(a+b+c)=1926
What is the a+b+c?
(6 marks)

Question 29
Sn where S is the sum of the digits of n.
Example: S1 -> S=1 and S29 -> S=2+9=11
What is the sum of S1+S2+S3+.......S2010+S2011?
(6 marks)

Note:
Sn-> n is a subscript
S1-> 1 is a subscript
S2-> 2 is a subscript
S3-> 3 is a subscript
S29-> 29 is a subscript
S2010-> 2010 is a subscript
S2011-> 2011 is a subscript

Thanks in advance for your time and effort to provide the worked solutions.

[YumYum]

Hi,


Can anyone help with this Qn :

Tony and Sam each have some money. If Tony spends $80 per day and Sam spends $40 per day, Tony will have $500 left when Sam has spent all his money. If Tony spent $40 each day and Sam spent $80 each day, Tony will have $1100 left when Sam has spent all his money. Find the amount of money Sam has.

thanks.

[Chan09]

Have another query:

A spent 3/10 of her salary on food, she spent 1/4 of the remainder on a luggage and $120 more on a toy than luggage. She had $468 left. How much was her salary?
Ans: $1680 :stupid:

[jieheng]

YumYum:

Hi,


Can anyone help with this Qn :

Tony and Sam each have some money. If Tony spends $80 per day and Sam spends $40 per day, Tony will have $500 left when Sam has spent all his money. If Tony spent $40 each day and Sam spent $80 each day, Tony will have $1100 left when Sam has spent all his money. Find the amount of money Sam has.

thanks.

If Tony spent $40 each day and Sam spent $80 each day, the ratio of the amount of money that Tony spent to the amount of money that Sam spent is $40 : $80 = 1 : 2

T [][-----1100-----] (1u+1100)

S [][]

If Tony spent $80 each day and Sam spent $40 each day, the ratio of the amount of money that Tony spent to the amount of money that Sam spent is $80 : $40 = 2 : 1 = 4 : 2

T [][][][][---500---] (4u+500)

S [][]

Compare the models of T ,

4u+500 -----> 1u+1100
3u -----> 600
1u -----> 200

The amout of money that Sam has = 2u = 2*200 = $400 (Ans)