Question

please tell me it's of maths I can't understand​

Answer 1

Answer:

Here the denominators are different. so you have to take LCM for the denominators 14, 21 to make into same.

Step-by-step explanation:

so LCM of 14, 21 = 2 x 7 x 3 = 42

$\frac{13}{14} \times \frac{3}{3} = \frac{39}{42}$

$\frac{15}{21} \times \frac{2}{2} = \frac{30}{42}$

Now we made the denominators as same.

Now we can subtract.

$\frac{39}{42} - \frac{30}{42} = \frac{9}{42}$

Then make into simplest form.Then is do cancellation.

$\frac{9}{42} = \frac{3}{14}$

(since it cancelled by a common factor 3.

So your answer is

$\frac{3}{14}$