Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
primary 6 | Maths
| Measurement
One Answer Below
Anyone can contribute an answer, even non-tutors.
PLS HELP ASAP
Date Posted: 5 years ago
Views: 376
let total number os $2 not be x and $5 be y.
total %5 amount is 5y which is 130 more than 2x,so
5y=130+2x
y is the number of $5 notes,$2 note is 19 more notes than $5 so x=y+19.Substitute this in eq1 we get,
5y=130+2(y+19)
5y=130+2y+38
5y=168+2y
3y=168
y=56
x=y+19
x=56+19=75
so total amount of $5 is 5 multipled by 56 which is 280
total %5 amount is 5y which is 130 more than 2x,so
5y=130+2x
y is the number of $5 notes,$2 note is 19 more notes than $5 so x=y+19.Substitute this in eq1 we get,
5y=130+2(y+19)
5y=130+2y+38
5y=168+2y
3y=168
y=56
x=y+19
x=56+19=75
so total amount of $5 is 5 multipled by 56 which is 280
Not a good method for students at the Primary 6 level who just started learning basic algebra.
The idea here is to make the number of pieces of $5 and $2 notes the same.
To make them the same, Ruth must either lose 19 pieces of $2 notes or gain 19 pieces of $5 notes.
Currently, the value of the $5 notes is $130 more than the value of the $2 notes. With a loss of 19 pieces of $2 notes (i.e. a drop of 19 x 2 = $38 in the value of the $2 notes), the new value of the $5 notes is 130 + 38 = $168 more than the new value of the $2 notes. Remember that the number of pieces of $5 notes and $2 notes is now the same.
For every 1 piece of $5 note and 1 piece or $2 note, their value difference is 5 - 2 = $3.
So for 2 pieces each, their value difference is $6. For 3 pieces each, their value difference is $9. And so on.
If the value difference is $168, there must have been 168/3 = 56 pieces each. So there are 56 pieces of $5 notes and 56 pieces of $2 notes at the end.
Before the loss, there must have been 56 pieces of $5 notes and 75 pieces of $2 notes.
The total value of the 56 pieces of $5 notes is 56 x 5 = $280. The total value of the 75 pieces of $2 notes is 75 x 2 = $150. Their value difference is $130.
————————————
You can also pretend that Ruth gains 19 pieces of $5 notes instead.
With this gain, the value of the $5 notes has increased by 19 x 5 = $95.
Now, the value of all the $5 notes is $225 more than the value of all the $2 notes.
For every 1 piece of $5 note and 1 piece or $2 note, their value difference is 5 - 2 = $3.
So for 2 pieces each, their value difference is $6. For 3 pieces each, their value difference is $9. And so on.
If the value difference is $225, there must have been 225/3= 75 pieces each. So there are 75 pieces of $5 notes and 75 pieces of $2 notes at the end.
Before the gain, there must have been 56 pieces of $5 notes and 75 pieces of $2 notes.
The total value of the 56 pieces of $5 notes is 56 x 5 = $280. The total value of the 75 pieces of $2 notes is 75 x 2 = $150. Their value difference is $130.
To make them the same, Ruth must either lose 19 pieces of $2 notes or gain 19 pieces of $5 notes.
Currently, the value of the $5 notes is $130 more than the value of the $2 notes. With a loss of 19 pieces of $2 notes (i.e. a drop of 19 x 2 = $38 in the value of the $2 notes), the new value of the $5 notes is 130 + 38 = $168 more than the new value of the $2 notes. Remember that the number of pieces of $5 notes and $2 notes is now the same.
For every 1 piece of $5 note and 1 piece or $2 note, their value difference is 5 - 2 = $3.
So for 2 pieces each, their value difference is $6. For 3 pieces each, their value difference is $9. And so on.
If the value difference is $168, there must have been 168/3 = 56 pieces each. So there are 56 pieces of $5 notes and 56 pieces of $2 notes at the end.
Before the loss, there must have been 56 pieces of $5 notes and 75 pieces of $2 notes.
The total value of the 56 pieces of $5 notes is 56 x 5 = $280. The total value of the 75 pieces of $2 notes is 75 x 2 = $150. Their value difference is $130.
————————————
You can also pretend that Ruth gains 19 pieces of $5 notes instead.
With this gain, the value of the $5 notes has increased by 19 x 5 = $95.
Now, the value of all the $5 notes is $225 more than the value of all the $2 notes.
For every 1 piece of $5 note and 1 piece or $2 note, their value difference is 5 - 2 = $3.
So for 2 pieces each, their value difference is $6. For 3 pieces each, their value difference is $9. And so on.
If the value difference is $225, there must have been 225/3= 75 pieces each. So there are 75 pieces of $5 notes and 75 pieces of $2 notes at the end.
Before the gain, there must have been 56 pieces of $5 notes and 75 pieces of $2 notes.
The total value of the 56 pieces of $5 notes is 56 x 5 = $280. The total value of the 75 pieces of $2 notes is 75 x 2 = $150. Their value difference is $130.
See 1 Answer
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
Here
Date Posted:
5 years ago
hi but can you write it in form of equation
In equation form, it will look like this. Note that this is more suitable for secondary students. The other tutor has written the equation form which is more for Sec 2 students, which I will do so here by your request.
Let the number of $5 notes be 1 unit. Since there are 19 more pieces of $2 notes than $5 notes, the number of $2 notes must be 1 unit + 19.
Now, since there are 1 unit pieces of $5 notes, their total value is 5 units (just like if you have three pieces of $5 notes, its total value is 3 x 5 = $15)
Since there are (1 unit + 19) pieces of $2 notes, we can say thatcher their total value is 2 units plus a further $38.
Values:
$5 —> 5 units
$2 —> 2 units + $38
Since the value of the $5 notes is $130 more than that of the $2 notes,
5 units = 2 units + 38 + 130
3 units —> 168
1 unit —> 56
Value of $5 notes
= 5 units
= 5 x 56
= $280
Let the number of $5 notes be 1 unit. Since there are 19 more pieces of $2 notes than $5 notes, the number of $2 notes must be 1 unit + 19.
Now, since there are 1 unit pieces of $5 notes, their total value is 5 units (just like if you have three pieces of $5 notes, its total value is 3 x 5 = $15)
Since there are (1 unit + 19) pieces of $2 notes, we can say thatcher their total value is 2 units plus a further $38.
Values:
$5 —> 5 units
$2 —> 2 units + $38
Since the value of the $5 notes is $130 more than that of the $2 notes,
5 units = 2 units + 38 + 130
3 units —> 168
1 unit —> 56
Value of $5 notes
= 5 units
= 5 x 56
= $280
THANK YOU!!
360 Tutoring Program