Sandhya secured 630 marks out of 900 and Monica secure 650 marks out of 1300 whose performance is better

Sandhya performed better.

Step-by-step explanation:

You can either or simplify the fractions:

and to simpler forms like and from there you can make the and multiply it by to get and then from there you can see Sandya performed better.

OR

You can divide 630 by 900 and 650 by 1300

630/900 gives you 70

and

650/1300 gives you 50

Clearly, once again Sandhya performed better.