Sums of Anarchy on Instagram: "The sevens seem to be the table that many people struggle with and although, if we’ve learnt our other tables, we don’t need to learn the sevens, here’s a tip you might find helpful: 🧠 To multiply by 7 we can count up in fives then keep counting but in twos. e.g. 6x7 Count up in fives 6 times (because it’s 6x7) 5, 10, 15, 20, 25, 30 Then keep counting but in twos: 32, 34, 36, 38, 40, 42 6x7=42 😎 For more mathemagical tips and tricks, check out our fantastic times

best explanation of two's complement representation and Overflow