Question

Explain why 7*13*5+7*6*5*3 is a composite number

Answer 1

Hi friend ,

7×13×5+7×6×5×3 is a composite number as:

7( 1×13×5 +1×6×5×3) [ Take 7 as common]

7( 65+90)

7( 155)

7( 5×31)

7×5×31

Since the fundamental theorm of arithmetic states that every composite number is a product of it's prime .Hence this is a composite number.

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Hope this helped u...

Answer 2

Composite number are those which have factors other than 1 and the number itself.

Now the given number is
7×13×5+7×6×5×3
Taking 7×5 common
7×5×(13+6×3)
7×5×31
Since the given number have factors (7,5,31) other than 1& number itself
So it is a composite number

Hope it will help you
best wishes --Mayank