Q&A - P3 Math

[elkniwt]

Hi,


Pls help solve this problem :
Anne and Bobby had a total of $309. After Anne spent $48 and Bobby saved $15, Anne has 2 times as much as Bobby. How much did Anne and Bobby have at first?

Thanks.

[tianzhu]

elkniwt:

Anne and Bobby had a total of $309. After Anne spent $48 and Bobby saved $15, Anne has 2 times as much as Bobby. How much did Anne and Bobby have at first?

Hi

One way to look at this question.

The amount Anne and Bobby left in the end is due to two transactions.

1) Anne spent $48 , which is a outflow
2) Bobby saved $15, which is an inflow.

Therefore, the original amount is reduced by (48-15) which is 33.

The final amount is (309-33) which is 276.

3 units ----276
1 unit -----92

At first

Anne ------ ( 2*92)+48 -----232
Bobby -----92 -15 -----77

Best wishes

[elkniwt]

Thanks for your help, Tianzhu!!!


I thought "saved" is considered outflow (as in out of the "what you have on hand" to a piggy bank or something)

I don’t have the answer, have to wait for the teacher to return paper. Thanks!

[tianzhu]

Hi elkniwt


Good Morning.

For this question, I interpreted it as Bobby had some extra money from some sources and saved $15.This amount is added to his original amount ($77).

I may be wrong.The best person is to check with the person who crafted the question.

Best wishes

[teh_oh]

A bicycle has 2 wheels.

A tricycle has 3 wheels.

How many bicycles and tricycles are there if there are 22 wheels altogether?

Ans key: 2 bicycles and 6 tricycles.

I want to confirm if the answer 8 bicycles and 2 tricycles is also acceptable (8x2+2x3)
And are there any other way to solve besides trial and error for this question?

Thanks.

[tianzhu]

teh_oh:

A bicycle has 2 wheels.

A tricycle has 3 wheels.

How many bicycles and tricycles are there if there are 22 wheels altogether?

Ans key: 2 bicycles and 6 tricycles.

I want to confirm if the answer 8 bicycles and 2 tricycles is also acceptable (8x2+2x3)
And are there any other way to solve besides trial and error for this question?

Hi teh_oh

Good Morning.

There are multiple answers to your question.

6T 2B
4T 5B
2T 8B
0T 11B

I think some information is missing from your question. Is the total number of bicycles and tricycles given?

I guess your question is similar to the “Counting heads and legs” type and besides Guess and Check(usually used in lower primary), a heuristics known as Making a Supposition or Assumption method is commonly used.

Compare your question with this one and see the difference. You’ll get only one answer for this question.

1.Lincoln visited a farm where he saw some cows and ducks. There were 75 of them. He then counted the legs of the animals and found that there were 220. How many animals of each type were there in the farm? (35,40 )

Best wishes

[teh_oh]

tianzhu:

teh_oh:

A bicycle has 2 wheels.

A tricycle has 3 wheels.

How many bicycles and tricycles are there if there are 22 wheels altogether?

Ans key: 2 bicycles and 6 tricycles.

I want to confirm if the answer 8 bicycles and 2 tricycles is also acceptable (8x2+2x3)
And are there any other way to solve besides trial and error for this question?

Hi teh_oh

Good Morning.

There are multiple answers to your question.

6T 2B
4T 5B
2T 8B
0T 11B

I think some information is missing from your question. Is the total number of bicycles and tricycles given?

I guess your question is similar to the “Counting heads and legs” type and besides Guess and Check(usually used in lower primary), a heuristics known as Making a Supposition or Assumption method is commonly used.

Compare your question with this one and see the difference. You’ll get only one answer for this question.

1.Lincoln visited a farm where he saw some cows and ducks. There were 75 of them. He then counted the legs of the animals and found that there were 220. How many animals of each type were there in the farm? (35,40 )

Best wishes

Hi Tianzhu,
Thanks for the replies. My question is extracted from a CA1 paper. I guess there must be many answers since there are no other information given. Thanks.


1.Lincoln visited a farm where he saw some cows and ducks. There were 75 of them. He then counted the legs of the animals and found that there were 220. How many animals of each type were there in the farm? (35,40 )

Thanks for the reference. I have bookmarked your solution to this similar question.

[b_vian]

Dear All,


Pls help me out in the following problem sum:-

Some sparrow were perching on two branches of a tree. THere were 5 more sparrows on the first branch at first. Then 4 sparrows flew from the first branch to the second one. WHich branch of the tree would have more sparrows? How many more sparrows were there?
:?:

[Pen88n]

2nd branch and 3 more sparrows.


Before:
1st branch: 1 unit + 5
2nd branch: 1 unit

After:
1st branch: 1 unit + 1
2nd branch: 1 unit + 4

Difference 3 more sparrows on 2nd branch

[24hr-mum]

got this question from andrew er’s maths companion p3 bk but no working shown in the bk. only ans.

how to do this without algebra?

if aziz buys 6 pens, he will have $6 left
if he buys 8 pens, he will be short of $2.
how much $ does he have?

---------

henry has some apples
when he puts them equally into boxes of 3, he will have 5 more boxes than if he puts them into boxes of 4. how many apples does he have?