Question

a and b are two positive integer such that the least prime factor of a is 3 and the least prime factor of b is 5. Then calculate the least prime factor of (a+b).....

ít íѕ vєrч ímpσrtαnt fríєndѕ plєѕαє hєlp mє....

Answer 1

Least prime of a is 3
Least prime of b is 5
Therefore least prime of a+b=3+5
a+b=8
a+b=2×2×2
Therefore least prime of a+b is 2

Answer 2

Since 3 is the least prime factor of a, therefore a is multiple of 3. So, we consider a= 12 ( with 3 as the least p.f.)

Similarly, b= 30 ( with 5 as the least prime factor)

Now, a+b= 12+30 = 42.

Factorizing 42, we obtain

42= 2x3x7, where 2 is the least value of prime factor for 42.

Hence, the ans is 2.
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