Practice problem
Can you calculate 50×1950\times 1950×19 in your head?
50×(20−1)50\times (20-1)50×(20−1)
50×(19+1)50\times (19+1)50×(19+1)
50×(21−1)50\times(21-1)50×(21−1)
50×19−50×150\times 19-50\times 150×19−50×1
Type a concept, like “slope” or “photosynthesis”.
