At Apple, 54% are white and 69% are males. A year after releasing their demographics, Google provided an update, 70% of the jobs at Google were held by men and 60% of the workforce was white (with 31% Asian). It's pretty blatant when looking at the numbers.
What to do about it?
Sara Mei wrote a blog post about how tech companies can solve their problem. In the article she lists a number of step:
If you need more help (after you read her article), then watch the Facebook Training on Managing Unconscious Bias. It's their staff training on dealing with issues in the workplace which end up causing the drastic homogeneous problem present in tech.