Hi Mike, i think you've made a mistake when explaining the sufficiency of statement 2. You combined it with the fact that N = ab where b=6+a (as stated in statement 1). Statement 2 should be sufficient by itself since when b=9 (the max single digit that it can have),N=4(9)-4= 32 which is definitely less than 40, so whatever number less than that will always be <40 so N<40. Thx again for all the explanations and keep up the good work :)
Hey Claudia! You're absolutely right. We only need to see that 4(9) - 4 = 32 is less than 40 to conclude that all N are less than 40 and statement 2 alone is sufficient. I've made a note so we can fix this. Thanks for pointing this out! :)
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