Here is a trick I use and have taught everyone in office. My co-workers love me for this.
Step 1: Insert the image in Microsoft word and select it.
Step 2: Select Remove background option from the Format ribbon.
Step 3: Drag and select the area that contains the image. The area that will be removed will be covered in pink and the object would be showing its original colour. In case it is a slightly complex image use the Mark areas to keep and Mark areas to remove buttons. When you're satisfied with your image select keep changes
Step 4: After you are done, right click on the image and select Save As Picture option and save the image in PNG format (this is extremely important to retain the transparency). Do not save as a JPEG/JPG.
And voila! your white background is removed!
Hope this helps!