Hi Moni,

First put your x data in A1 to A6 and your y data in B1 to B6.
Then highlight your data and go to insertchart.
In the chart wizard select xy scatter and click next.
In the next window check columns and click next
This next window is only for formatting purposes
and can be bypassed by clicking finish.

Now in your chart right click on one of the data points and
select Add Trendline. Select linear, click on the options tab
and check 'display equation on chart' then OK.

You will now have a line of best fit through your data
and an equation for that line in the form of Y=Mx+C
where M is the gradient (SLOPE function)
and C is the Y-intercept (INTERCEPT function)

Now put this formula in E1
=(D1-(INTERCEPT(B1:B6,A1:A6)))/SLOPE(B1:B6,A1:A6)

Now you can plug any y value into D1 and E1 will return
the x value.

Note that this is not exact as your data doesn't fit
a linear regression exactly, however in your example
it is very close.

HTH
Martin