what is r (10) when r = 8.2 i dont know it

So when it says: r (10) and r=8.2, it's basically saying the r (which equals 8.2) is multiplied by 10! So all you would do it take 8.2 (Which is r) and multiply it by 10! You can use a calculator for this if you would like too! Or you could just use mental math! The answer would be 82!