Who then is the genius???

I remember back then in school,2015 to be precise,was with my reading partners studying for our final exams. A fresher from God knows where just came by asking what 7x13 was.
Honestly I was expecting a cold reply from my sociology friend,instead she was like;

''7x13??? errmmm errmmm come ooo how does the answer affect our environment? U should focus on exploring the organization of knowledge production in systems biology, which is a research approach that brings together biologists, physicists, engineers, mathematicians and computer scientists in novel interdisciplinary arrangements not what 7x13 is. I was dumbfounded,as her reply was totally off point and uncalled for.

Just as i was about to laugh and scold fash at the same time, my other mate in person of Loyce made matters worse. Loyce is a political scientist. And so,he started;

Fasola Nooo!!! Noo!!! Nooo!!! Listen to my argumentum propentum, u see, 7*13 looking at it from the political angle,since we all r political animals, the answer can and should be traced back to Plato who happens to be the modern political science study of political behavior through survey samples of a population, controlled experiments, and other data collection methods that can be statistically analyzed to get the answer you're looking for. And so out of annoyance I replied "ohhhh please just answer the God damn question already or are your brains hibernating?

Alex,another mate,a psycologist replied. Don't mind them dear. They probably can't remember or never really learned how to do some of this stuff and they thought it was hard. Maybe as a kid they even decided that they were going to hate math. But here's some good news: the above question is much easier as an adult! Why? Primarily because you are more motivated, more matured and experienced,so you know how to study and ask questions, and because as an adult you won't tolerate lazy or confusing math teachers. You have many good options. They are:

1. Take a basic math class that answers the question. One class should be enough. (Note: “Business Math” is a math class that applies the above topics to common business situations. These classes are useful, but probably best to take after you have completed a basic math class if you want additional review.)
2. Use a math tutor or math lab at school.
3. Do your own math review for only what you need. There are many good basic math books available. Just be sure that they contain lots of examples and problems with complete and detailed solutions.
   
   At this point, fash,loyce and myself started asking what we were talking about.
   So as the boss or smartest that i am,i decided to end this rubbish! I am an Economist so i wanted to answer the question like a boss,throw shades at them and walk away.

So i started. Guyz the answer is 91 but if not just tell me what u think it is and i'll come up with a theory to prove u wrong and we'll both be right cuz economists are always right.
Hold on a second,where is the boy that asked this question???
It's 2018 and we are still looking for him to give him the answer.
All images are from google.com