Q&A - P5 Math

[2Transformer]

Please help on the following questions:-


1. Mr. Yong gave $840 of his salary to his mother and gave 1/5 of his remaining salary to his wife. If he had 1/3 of his salary left, how much was his salary?

2. Robert wanted to buy 12 erasers but he found that he was short of $0.80. If he bought 8 erasers, he would have $1.60 left over. How much money did Robert have?

3. There were 3/4 as many students in Camp A than in Camp B. After 25 pupils joined Camp B, the ratio of the number of students in Camp B to Camp A becomes 7:4. Find the number of students in Camp B at first.

[chloecube]

MathIzzzFun:

chloecube:

Three team A,B&C participated in a competition. There were 34 pupils in team B & C. If 22 pupil were not in team B n 28 pupil were in team C,how many pupil were there altogether in the three teams?

22 pupils not in Team B means
Team A & C --> 22

28 pupils not in Team C means
Team A & B --> 28

Team B & C --> 34

Total number of pupils in Team A & B & C --> (22 + 28 + 34) / 2 = 42

cheers.

:thankyou:

[MathIzzzFun]

2Transformer:

Please help on the following questions:-


1. Mr. Yong gave $840 of his salary to his mother and gave 1/5 of his remaining salary to his wife. If he had 1/3 of his salary left, how much was his salary?

Remainder --> 5 units
wife --> 1 unit
Left --> 4 units = 1/3 of salary
salary --> 12 units

12 units - 5 units = 7 units --> $840
1 unit --> $ 120

salary --> 12 x $120 = $ 1440

cheers.

[MathIzzzFun]

2Transformer:

Please help on the following questions:-


2. Robert wanted to buy 12 erasers but he found that he was short of $0.80. If he bought 8 erasers, he would have $1.60 left over. How much money did Robert have?

http://i39.tinypic.com/vqieps.png\">

4 erasers --> $ 1.60 + $0.80 = $ 2.40

1 eraser --> $ 0.60

Robert's money --> 8 x $ 0.60 + $ 1.60 = $ 6.40

cheers.

[MathIzzzFun]

2Transformer:

Please help on the following questions:-


3. There were 3/4 as many students in Camp A than in Camp B. After 25 pupils joined Camp B, the ratio of the number of students in Camp B to Camp A becomes 7:4. Find the number of students in Camp B at first.

The number of students in Camp A remained the same, so make the ratio part for Camp A the same in the \"start\" and \"end\" ratios.

At first, students in Camp A : Camp B = 3 : 4 --> 12u : 16u
In the end, students in Camp A : Camp B --> 4 : 7 --> 12u : 21u

Increase in number of students in Camp B = 21u - 16u = 5u

5u --> 25
1u --> 5

At first, number of students in Camp B --> 16 x 5 = 80

cheers.

[cookieandmonster]

Please help with this question:


Peter had 632 stamps and Freddy had 80 stamps. After their father had given them each an equal number of stamps, Peter had 5 times as many stamps as Freddy. How many stamps did their father give to each of them?

[Oldschool]

cookieandmonster:

Please help with this question:


Peter had 632 stamps and Freddy had 80 stamps. After their father had given them each an equal number of stamps, Peter had 5 times as many stamps as Freddy. How many stamps did their father give to each of them?

Hi,

Father gave each of them U stamps, so

632 + U = 5(80 + U)
632 + U = 400 + 5U
U = 58

Regards

[2Transformer]

MathIzzzFun:

2Transformer:

Please help on the following questions:-


1. Mr. Yong gave $840 of his salary to his mother and gave 1/5 of his remaining salary to his wife. If he had 1/3 of his salary left, how much was his salary?

Remainder --> 5 units
wife --> 1 unit
Left --> 4 units = 1/3 of salary
salary --> 12 units

12 units - 5 units = 7 units --> $840
1 unit --> $ 120

salary --> 12 x $120 = $ 1440

cheers.

:thankyou: MathIzzzFun !! My son likes ALL your explaination.

[2Transformer]

MathIzzzFun:

2Transformer:

Please help on the following questions:-


2. Robert wanted to buy 12 erasers but he found that he was short of $0.80. If he bought 8 erasers, he would have $1.60 left over. How much money did Robert have?

http://i39.tinypic.com/vqieps.png\">

4 erasers --> $ 1.60 + $0.80 = $ 2.40

1 eraser --> $ 0.60

Robert's money --> 8 x $ 0.60 + $ 1.60 = $ 6.40

cheers.

:thankyou:

[2Transformer]

MathIzzzFun:

2Transformer:

Please help on the following questions:-


3. There were 3/4 as many students in Camp A than in Camp B. After 25 pupils joined Camp B, the ratio of the number of students in Camp B to Camp A becomes 7:4. Find the number of students in Camp B at first.

The number of students in Camp A remained the same, so make the ratio part for Camp A the same in the \"start\" and \"end\" ratios.

At first, students in Camp A : Camp B = 3 : 4 --> 12u : 16u
In the end, students in Camp A : Camp B --> 4 : 7 --> 12u : 21u

Increase in number of students in Camp B = 21u - 16u = 5u

5u --> 25
1u --> 5

At first, number of students in Camp B --> 16 x 5 = 80

cheers.

:thankyou: MathIzzzFun, thank you for your detailed n yet simple explaination. I really appreciate it.