Teen Math

Pia is preparing for he NAPLAN exams.  We want to make sure her math is solid.  School has just started after a month and a half of Christmas vacation, so she’s rusty.

She has to multiply 73 x 72. Multiplying 7 x 2, she knows the answer is 14, but not sure  whether to write down the ‘4’ or the ‘1’.

Pia: Daddy, should I write the four or the teen?

* * *