Q&A - P3 Math

[bbc]

Thanks, PapayaDad.

[vinegar]

Mary thinks of a 2-digit number.When the number is divided by 5, the remainder is 3.When the number is divided by 9, th remainder is 1. What is the number?

[vinegar]

Ali has 318 story books. If she wants to donate 7 story books to each of her students, what is the maximum number of students she can donate to?

[sembgal]

318 divided by 7= quotient and remainder.

Quotient: 45. The answer for number of students
Remainder = 3. The answer for remaining books.
Take the quotient as the answer.

[sembgal]

vinegar:

Mary thinks of a 2-digit number.When the number is divided by 5, the remainder is 3.When the number is divided by 9, th remainder is 1. What is the number?

The answer is 40.
Working: 5 + 3 = 8
9 + 1 =10
The first common multiple of 8 and 10 is 40
8, 16, 24, 33, 40
10, 20, 30, 40

[ammonite]

sembgal:

vinegar:

Mary thinks of a 2-digit number.When the number is divided by 5, the remainder is 3.When the number is divided by 9, th remainder is 1. What is the number?

The answer is 40.
Working: 5 + 3 = 8
9 + 1 =10
The first common multiple of 8 and 10 is 40
8, 16, 24, 33, 40
10, 20, 30, 40

? 40 divided by 5 is 8, no remainder leh.

I don't know what the standard method is, but through deduction, my answer is 28.

[vinegar]

vinegar:

Mary thinks of a 2-digit number.When the number is divided by 5, the remainder is 3.When the number is divided by 9, th remainder is 1. What is the number?

Anyone? How to teach? Is there a modeling? :?:

[sembgal]

ammonite:

sembgal:

[quote=\"vinegar\"]Mary thinks of a 2-digit number.When the number is divided by 5, the remainder is 3.When the number is divided by 9, th remainder is 1. What is the number?

The answer is 40.
Working: 5 + 3 = 8
9 + 1 =10
The first common multiple of 8 and 10 is 40
8, 16, 24, 33, 40
10, 20, 30, 40

? 40 divided by 5 is 8, no remainder leh.

I don't know what the standard method is, but through deduction, my answer is 28.[/quote]Sorry, mistake on my part. Thanks for highlighting to me.
Working:
For Groups of 5 with remainder 3
5, 10, 15, 20, 25
If add 3= 8, 13, 18, 23, 28

For Groups of 9 with remainder 1
9, 18, 27
If add 1= 10, 19, 28

The answer is 28

[vinegar]

thanks sembgal…


will be great if there is someone able to modelize it

[vinegar]

another question:


Lynn has a box of 153 buttons.If she needs another 7 buttons so that every blouse she sews can have 5 buttons, how many blouses has she sewn?