Answer:
Children must have the right to an education.
Government must serve to better the lives of a society's citizens.
A government foreign to its people should not decide innocence or guilt.
Colonial rule has not benefited the country that has been colonized.
People have an inherent human right to justice.
Step-by-step explanation:
I am most sure on including "people have an inherent human right to justice"; both Gandhi and Mandela believed in justice.
Furthermore, the one that cannot be included is "society must engage in capitalism to fulfill its destiny". Gandhi was fiercely against capitalism.
Another that should be included is "colonial rule has not benefited the country that has been colonized". Both Gandhi and Mandela lived under colonist governments, and protested against the bad treatment they got.
On the statement of "a government foreign to its people should not decide innocent or guilt", I think they would both agree with this. Even though Gandhi proposed not to have government, I think he would argue against a bad government that was "foreign to its people". Mandela, of course, argued for democracy, and would protest against a foreign government.
Children having a right to education is probably something both of them would support. I would have to look at the articles you were provided to better answer this, though.
Government must serve to better the lives of a society's citizens. This is obviously inherently Mandela's argument, and I think Gandhi would agree with it (it's what they argued for). The only caveat is if the article you read was one of Gandhi's anti-government (no government = best government) articles.
Hope this helps!