Q) A prime number greater than 3 is divided by 6. Which of the following can be the remainder of the mentioned division?
a) 1
b)2
c)4
d)5
e)both a and d
soln : To solve this problem all you need to know is a prime number greater than 3 can be expressed as 6k+1 or 6k-1. 6k+1 will give remainder 1 and 6k-1 will give 5 as a remainder. Hence E
Factors:
I asked my friend today to list all factors of 100 and this is what he did
1,2,4,5,10,20,25,50,100. This is how an untrained mind calculates factor. One important thing to note in factors is for every single factor you have one more corresponding factor known as factor pair. A trained mind should list factors in the form of factor pair.
Read rest of the topic in my blog(link in my signature) and any questions do let me know
Thanks,
Quant-Master
a) 1
b)2
c)4
d)5
e)both a and d
soln : To solve this problem all you need to know is a prime number greater than 3 can be expressed as 6k+1 or 6k-1. 6k+1 will give remainder 1 and 6k-1 will give 5 as a remainder. Hence E
Factors:
I asked my friend today to list all factors of 100 and this is what he did
1,2,4,5,10,20,25,50,100. This is how an untrained mind calculates factor. One important thing to note in factors is for every single factor you have one more corresponding factor known as factor pair. A trained mind should list factors in the form of factor pair.
Read rest of the topic in my blog(link in my signature) and any questions do let me know
Thanks,
Quant-Master
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