Question

cindy says she found a shortcut for doing multipication problems .when she multiplies 3 times 24 ,she says, 3 times 4 is 12 ones ,or 1ten and 2 ones . then there's just 2 tens left in 24, so add it up and you get 3 tens and 2 0nes ." do you think cindy's shortcut works ? explain your thinking in words to justify your response using a model or partial prouducts.

Answer 1

Yes she would be right and that is a smart short cut

Answer 2

No because 3 times 24 actually equals 72
she forgot to multiply the 2 tens by 3
if she would've done that the answer would be 7 tens and 2 ones
:-)