human
Recognise and use efficient methods for mental multiplication Tom and Katie are discussing ways to calculate \( 49 \times 9 \) mentally
Tom multiplies \( 49 \) by \( 10 \) and then subtracts \( 49 \) from the answer.
Katie does \( 50 \times 9 \) and then subtracts \( 9 \) from the answer
Who would get the correct answer? Only
Katie
gpt
Believes that the compensation strategy for the multiplication of 2 numbers can only be used one way round.