John read $10$ pages of his book in the first day of holiday. He is reading $4$ pages more than he read in every day. How many pages did John read till the end of the 8th day of holiday?
I know that this is just algebra. However, the important thing is to make the correct equations.
Let's call the amount of the pages $x$
First day: $10x$
till end of the 8th day: $10x+28$
On
The statement of this problem is very unclear you should consider revising.
However, I am reading it as John read 10 pages on the first day and four more pages each day. It seems like you are then trying to write equations (1) for the pages read on that day and (2) for the total pages read to that point.
$(1)$ Let $f(x)=10+4(x-1)$ where $x$ is the day and $f(x)$ is the pages John read that day.
$(2)$ The easiest way of writing this equation would be to use recursive series. Let $a_1=10$ because we know from the problem statement that John read 10 pages on day 1. Now, let $a_n=a_{n-1}+f(x=n)$
Thus, if you are looking to find how many pages John read on day 8 and the total pages John read up to that point you set $n=x=8$ and solve equations $(1)$ and $(2)$ giving you $f(8)=38$ and $a_8=a_7+f(8)=192$
The first day, John read $10$ pa ges. The second day, John read $10+x$ pages, where $x=4$, and so on.
He did this for $8$ days, and on the last day, John read $10+7x=38$ pages, where $x=4$
Therefore, you have to find the average of $10$ and $38$, and multiply it by the number of days, which is $8$.
Hint: (open if stuck)