Q12 of 104 Page 1

Show that 5 x 7 x 11 x 13 + 55 is a composite number.

Composite number: A whole number that can be divided exactly by numbers other than 1 or itself.


5 x 7 x 11 x 13 + 55


5 (1 x 7 × 11 x 13 +11)


5 × 11 (91 +1)


5 × 11 (92)


5 × 11 (22 × 23)


5 × 11 × 2 × 2 × 23


So, given number is the composite number because it is the product of more than one prime numbers.


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