1. ## simplifying

i need to know what this would be when simplified also i need to know how you did it thanks

21
---
35

2. To learn how to simplify fractions, try here.

3. i know how to do questions like these im just stuck on this 1 i wanna also know if the answer will be just be

21
---
35
or if it will be something like 10.5

4. Originally Posted by andyboy179
i know how to do questions like these im just stuck on this 1 i wanna also know if the answer will be just be

21
---
35
or if it will be something like 10.5
You have to examine the numerator and the denominator if they contain a common factor. With your example you get:

$\dfrac{21}{35} = \dfrac{7 \cdot 3}{7 \cdot 5} = \dfrac11 \cdot \dfrac35 = \dfrac35$

5. Originally Posted by earboth
You have to examine the numerator and the denominator if they contain a common factor. With your example you get:

$\dfrac{21}{35} = \dfrac{7 \cdot 3}{7 \cdot 5} = \dfrac11 \cdot \dfrac35 = \dfrac35$

what did u do to get 7.3 and 7.5

6. Originally Posted by andyboy179
what did u do to get 7.3 and 7.5
I assume that you have heard about prime decomposition (?): Each natural number can be written as a product of prime factors OR (if the number is a prime factor itself) as $1 \cdot number$.

The first prime numbers (which you should learn by heart) are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, ...

There are an infinite number of prime numbers.

I examined 21: It is divisible by 3 that means 3 must be a factor in 21. The remainder is 7 which is a prime factor too. Thus $21 = 3 \cdot 7$

Do the same with 35.

7. This seems way to obvious so it is probably wrong but..
Both 21 and 35 can be divided by 7.

$21/7 = 3$
$35/7 = 5$

So it simplified would just be $\dfrac{3}{5}$?