Question 1102605
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If an additional 22 marks raised the average per paper by 2, then the number of papers was 22/2=11.<br>
You don't need to do any calculations with the actual marks to find that answer.  But if you want to, it might look like this:<br>
let x be the number of papers<br>
Then since the average mark was 63, the total number of marks was 63x<br>
Now you are changing the total number of marks to 63x+20+2 = 63x+22.<br>
The new average is 65:<br>
{{{(63x+22)/x = 65}}}
{{{63+22/x = 65}}}
{{{22/x = 2}}}
{{{x = 11}}}