Incorrect answers in Calculator app on iPhone

The iPhone calculator is giving me wrong answers. If I attempt 10+10(divide by)2 as one sum, it gives me 15!? What the heck? See the screenshot image. If I press = and then divide by 2 it gives the correct answer 10.

Seriously, though, this is a phone and app developed by one of the most prestigious tech firms. Surely 10+10/2 in one sum is not too much to ask.

Anyone else finding this?

Thanks!

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