Dangerous calculate in your head -tips

I’ve been exposed to some calculate big numbers in your head -tips in social media. At first, I thought that’s nice. It’s good mental practice to use one’s own brain instead of calculator. But then when I look closer, I see that some of them are poorly defined.

Here is an example of squares of large numbers: 102 x 102 = 10404. The tip says: take the original number and add the last digit to it, so 104. Then, take the last digit and square it, use two digits. That means 04. Now these to should be concatenated like this: 10404. Seems to work. But the important question is when you can use this in the first place? There is no range mentioned in the tip.

Ok, you can say that this works for numbers 101,…,109. If you really want to make an effort and memorize this rule for those calculations, go for it. But I see a real danger that students are not so punctilious that they check all these tips before using them on any numbers (greater that 100.) This is bad for credibility of well formulated tips, too.

Best regards,
Concerned Math Teacher.

On the mercy of Twitter algorithms

This is not the key subject of this blog but I made some observations about Twitter. I might be wrong at some point, but it’s not likely. So, here comes 5 things that affects your visibility on Twitter.

1. Twitter’s own algorithms

Admit it or not, this is what really matters. If you follow, let’s say, more than 10 people only some tweets will be shown to you. Twitter algorithm chooses. Had some suggestions who to follow? Twitter algorithm. Had several users following you even if you didn’t do anything special? Twitter algorithm probably suggested you to some users.

2. Bots’ algorithms

We all know there are lots of bots out there. Sometimes they attach to some hashtags you used. Some obviously register new users and start to follow them. If you’ve registered (relative) recently, maybe you noticed that some social media marketing “persons” started to follow you out of the blue? We may also include some bot & human co-operated users here.

3. Change

Who will see your tweet? After all algorithm involving, who is even online at the right time? Who will type the right search word, who happens to retweet?

4. Networks

Yes, there are some nice networks boosting other users in the same specialized field, but there is only so far it can go. Social media marketing and blogs are the most active network boosters I’ve seen. And for some odd reason, wrestling.

5. You said something ingenious

Sometimes accidents will happen and someone sees what you’ve written. World would be nice place if this was the first on this list.

To sum up, algorithms don’t usually get me. If one day I like something, that subject will be shown in large scale the next day. But for person who is interested in various subjects, that’s restricting. It would be really valuable to know how these algorithms work, but I bet it isn’t public knowledge. Or, if there is even roughly similar platform that doesn’t do picking for you, I’ll give it a try.