A significant privacy flaw in the widely used instant messaging platform WhatsApp has reportedly exposed the phone numbers and profile photos of 3.5 billion people worldwide. Cybersecurity researchers ...

Adding larger numbers in your head is not always easy. If you need to use pen and paper, then the column method is a good way to add. It involves writing one number beneath the other, so that the ...

19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...