Q&A - P5 Math

[andyle.024255sg]

tianzhu:

purple05:

2. ½ of Joshua’s savings is equal to 4/5 of Megan’s savings. The difference between
their savings is $15. What is Megan’s total savings?


Ans = $25?

But when i work backwards I dun seem to get $25, is my ans correct?

Hi

Draw 5 boxes to show Megan’s savings. Shade 4 boxes.

Draw 8 boxes to show Joshua’s savings. Shade 4 boxes and try to align them with those of Megan.

Difference ------ 3 boxes

3 boxes ------ 15

1 box ------- 5

Megan’s total savings ------ 5 boxes ------- 25

Best wishes

Hi purple05,

The method is about using equivalent fractions. There are two fractions 1/2 and 4/5, we try to make the numerators of these fractions become the same to solve this exercise.

1/2 = 4/8
4/5 stays the same

Hence, we have 4/8 of Joshua's savings is equal to 4/5 of Megan's savings. We can use 4 boxes to represent this equal part. Thus, Joshua's savings is 8 boxes in total, while Megan's savings is 5 boxes in total.

The next step is basic and your child can easily continue.

Further Discussion: If the question gives: 3/4 of Joshua's savings = 4/5 of Megan's savings, then we can do as below:
3/4 = 12/16
4/5 = 12/15

Cheers.

[Jamesbond]

Lim distributed 300 souvenirs from the art museum to some girls in P4 and P5. Each P4 girl received 5 souvenirs and each P5 girl received 3 souvenirs. The P4 girls received 60 more souvenirs than those in P5. How many more P5 girls were there?

Pl help…

[purple05]

my method is 1/2-1/5 = $15

5/10-2/10 = $15
3 units = $15
1 unit = $5
5 units = $25

my method correct?

[speedmaths.012624com]

Jamesbond:

Lim distributed 300 souvenirs from the art museum to some girls in P4 and P5.
Each P4 girl received 5 souvenirs and each P5 girl received 3 souvenirs. The P4 girls received 60 more souvenirs than those in P5.
How many more P5 girls were there?

Hi,

Lim distributed 300 souvenirs,
The P4 girls received 60 more souvenirs than those in P5

P5 girls received (300 - 60) / 2 = 120 souvenirs,
P4 girls received (300 + 60) / 2 = 180 souvenirs,

Each P5 girl received 3 souvenirs,
There were 120 / 3 = 40 P5 girls

Each P4 girl received 5 souvenirs,
There were 180 / 5 = 36 P4 girls

40 - 36 = 4 (more P5 girls)

Hope this helps.

speedmaths.com

.

[Jamesbond]

speedmaths.com:

Jamesbond:

Lim distributed 300 souvenirs from the art museum to some girls in P4 and P5.
Each P4 girl received 5 souvenirs and each P5 girl received 3 souvenirs. The P4 girls received 60 more souvenirs than those in P5.
How many more P5 girls were there?

Hi,

Lim distributed 300 souvenirs,
The P4 girls received 60 more souvenirs than those in P5

P5 girls received (300 - 60) / 2 = 120 souvenirs,
P4 girls received (300 + 60) / 2 = 180 souvenirs,

Each P5 girl received 3 souvenirs,
There were 120 / 3 = 40 P5 girls

Each P4 girl received 5 souvenirs,
There were 180 / 5 = 36 P4 girls

40 - 36 = 4 (more P5 girls)

Hope this helps.

speedmaths.com

.

:thankyou:

[Jamesbond]

http://i46.tinypic.com/1z3wcr8.jpg\">

Pl help...

[andyle.024255sg]

Jamesbond:

http://i46.tinypic.com/1z3wcr8.jpg\">

Pl help...

Area of triangle ABF = 1/2 of Area of Rectangle ABEG
Area of triangle BDE = 1/2 of Area of Square BCDE
Hence, Area of the shaded = 1/2 of Area of the whole figure ACDG
= 1/2 * 50 * 16

Cheers.

[Breadandmuffins]

Hi, I have 3 qns:


1) At first, there were 234 more apples in Stall A than Stall B. After 78 apples were transferred fr Stall B to Stall A and 24 apples were thrown away fr Stall A, there were 4 times as many apples in Stall A as Stall B. How many apples were there in Stall B at first?

2) 6 pens cost as much as 2 notebooks. 7 pens cost $4.40 more than 1 note book.Danny spent $88 on an equal number of pens and notebooks. How many pens did he buy?

3) A class library had a total of 340 novels , fiction books and comics. After 3/7 of the novels and 25 comics were loaned out, and 30 fiction books were bought, the number of the three types of books were the same. How many comics did the class library have at first?

Tjank you.

[PapayaDad]

1) At first, there were 234 more apples in Stall A than Stall B. After 78 apples were transferred fr Stall B to Stall A and 24 apples were thrown away fr Stall A, there were 4 times as many apples in Stall A as Stall B. How many apples were there in Stall B at first?


In the end :

A:uuuu
B:u

At first :

A:4u-78+24 (before B give A 78 and also before A throw 24)
B:u+78 (before giving 78 to A)

At first A is 234 more than B ie. A-B=243 so
4u-78+24-u-78=243
3u=234+78-24+78=366
u=122
at first b=122+78 = 200

check

at first A have 434
B give A 78 ; B left 122, A become 512 ; then A throw 24 left 488
488 is 4 times of 122 - correct

[PapayaDad]

2) 6 pens cost as much as 2 notebooks. 7 pens cost $4.40 more than 1 note book.Danny spent $88 on an equal number of pens and notebooks. How many pens did he buy?


6p=2n or 2n=6p so
n=3p

p:u
n:3u

7p (7u) is $4.40 more than n(3u)
7u-3u=$4.40
4u=$4.40
u=$1.10

p=$1.10 ; n=$3.30
1p+1n=$4.40
$88/$4.40 = 20

Answer : 20p and 20n