how to compress jpeg to reduce size

[Tapas Mishra]

I have an image which is 1.7Mb in size it is a scanned document.
I have to submit it online in an application where they do not accept
more than 1 Mb size JPEG
so how can I reduce the size of this image.Any format other than this
gif,png,jpg also is acceptable but
file size should be 1 Mb only.So how can I achieve this let me know if
some one has any suggestions for the same.

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Thanks