Maths puzzle leaves adults stumped – as only those who are ‘highly intelligent’ can solve it

This maths puzzle has left adults completely and utterly stumped, not knowing what the answer is – but do you think you’ll be able to answer it? Why not give it a go?This maths puzzle has left adults completely and utterly stumped, not knowing what the answer is – but do you think you’ll be able to answer it? Why not give it a go?