CHEWY MATH TUITION CENTRE

Unleash Their Potential!

Chewy Math is founded in October 2014. We believe in the potential in every child to do well. Through the star chart and reward system, we aim to make learning easy yet fun. With a smaller class size and step by step learning approach, we help the children to understand the creative and fun concepts. We also encourage the children to think on their feet and being able to solve the question independently. They will thus gain confidence and do even better and their potential will be unleashed.

Interesting Concept 2: Units


1 km => 1000m
1 kg => 1000g
1 litre => 1000ml =>1000cm3 (cubic centimetre)

Only this is different:
1m => 100cm

OTHERS:
Annually - every year
Monthly - every month
Weekly - every week
Dozen - 12

1 hour - 60 minutes - 3600 seconds
1 minute - 60 seconds

Interesting Concept 1: Order of operations


Method 1: Royalty
Brackets (Castle)
Multiply/ Divide (King & Queen)
Plus/Minus (Prince & Princess)
=> Left to Right

We need to solve those in the Castle first. For the equation in the bracket, the king/queen followed by prince/princess rule still follows.
And it's always left to right rule if both (only king and queen) or (only prince and princess) are in the equation.

Method 2: BODMAS
Bracket
Order
Divide
Multiply
Addition
Subtraction

Dear Parent,


Chewy Math is founded in October 2014. We believe in the potential in every child to do well. Through the star chart and reward system, we aim to make learning easy yet fun. With a smaller class size and step by step learning approach, we help the children to understand the creative and fun concepts. We also encourage the children to think on their feet and being able to solve the question independently. They will thus gain confidence and do even better and their potential will be unleashed.

In this forum, I will be posting interesting concept and questions. To open up for discussion.

Concept: Repeated Identity


Mary and Jenny had a number of stickers in the ratio 4: 1. Jenny and Grace had a number of stickers in the ratio 2: 3. If they have a total of 169 stickers altogether, how many stickers does Mary have?

Exam tips!!
1. Highlight the key words
2. Identify the concept: Repeated identity
3. Write down the info provided in the question

Whose name is repeated twice? JENNY!!
M : J
4 : 1 (multiply by 2 to make Jenny's ratio the same)

J : G
2 : 3

Put the ratio together to compare
M : J : G
8 : 2 : 3
Total units = 8 + 2 + 3 = 13

13 units -> 169 stickers
1 unit -> 13 stickers
8 units -> 104 stickers
Mary has 104 stickers

** Repeated identity questions can be in the form of percentages, fractions and ratio.

Hi jwxh,


Thank you for the qn. I welcome more questions

A stapler cost $8. A dictionary cost $12.50. Tom bought 9 staplers and dictionaries. He paid $31 more for the staplers than the dictionaries. How many dictionaries did tom buy?[/quote]


Method 1: Algebra
Let the number of stapler be x. Let the number of dictionary be y.
Equation 1: x + y =9
Equation 2: 8x - 12.5y = 31

From eqn 1, we can say that x = 9 - y
Then we substitute x = 9 - y into eqn 2.
8 (9 - y) - 12.5y = 31
72 - 8y - 12.5y = 31
12.5y + 8y = 72 - 31
20.5y = 41
y = 2
Thus, he bought two dictionaries.

Method 2: Assumption method
Assume that Tom has spent all his money on staplers
9 x $8 = $72

Take out the $31 more that he spent on staplers
$72 - $31 = $41

Now we can add up the amount of a stapler and a dictionary
$12.50 + $8 = $20.50 (1 set of stapler and dictionary)

Divide
$41 / $20.50 = 2
Thus, he bought two dictionaries.


EXAM TIPS: If you have time, you can check the answer.
Dictionary: 2 x $12.50 = $25
Staplers: 7 x 8 = $56
Difference: $56 - $25 = $31

2) Concept: Constant difference (Ratio)


The ratio of Martin's age to Jeremy's age is 1:4. In 15 years time, the new ratio is 2:3. How old is Martin now?

Note: The age difference/ age gap always remain the same.
Thus, we have to make both difference the same.
1:4 (difference is 3 units)
2:3 = 6:9 (multiply by 3 to have the difference of 3 units)

Difference:
Martin: 1 unit to 6 units (Diff: 5u)
Jeremy: 4 units to 9 units (Diff: 5u)
Thus, the 5 units will be the growth of 15 years
5 units => 15
1 unit => 3
Martin is 3 years old now.

Dear Parents,


If you have any Math questions, please feel free to post here. I will get back as soon as possible. I will also post common exam questions weekly so do check out my post frequently.

1) Concept: External unchanged (Ratio)

On a train, the ratio of the male to the number of female passengers was 5:9. After 20 female alighted, the ratio became 1:3. How many female passengers were there on the train at first?

Note: The number of male passengers remained unchanged. Only female passengers alighted.
Before -> 5:9
After -> 1:3 = 3:9 (muliply by 3 to make both male units the same)
Now we can compare the female units, notice there was a decrease from 5 units to 3 units (difference of 2 units)

Thus, the 2 units equates to the 20 female passengers.
2 units -> 20
5 units -> 50

There are 50 female passengers on the train at first.