hails the maths queen

John and Mary competes in a race. John competes with four times as many boys as girls.
Mary competes with five times as many boys as girls.
How many children are there in the race??

Sad to say, i cant solve a pri 5 question.
ironically i've been teaching secondary school maths quite well i must say.(hehe)
well...karima, jiaxin, huishan n my ehem.. took up the challenge.

i must say its a close fight btw karima n hmmm...
he got the answer
karima got the method

but being the erm woman that i am

i declare karima the the champion!