Five children are playing a game. Three more children join in. Which of these tells you how many children are there in total? Five take away three, five plus three, or eight plus three.
There are five children playing a game and three more children join in. There’s a group of five children and a group of three children. Five and three is the same as saying five plus three.
The number sentence which tells us how many children are there in total is five plus three.