7,8,9,10 all with primes 2,3,5,7 less than self. Not D (with 11) as 2x3x5x7x11 is not 210.

C= 4. 7,8,9,10 all with primes 2,3,5,7 less than self. Not D (with 11) as 2x3x5x7x11 is not 210.

— Britten Mathematics (@BBMaMaths) February 27, 2018

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7,8,9,10 all with primes 2,3,5,7 less than self. Not D (with 11) as 2x3x5x7x11 is not 210.

C= 4. 7,8,9,10 all with primes 2,3,5,7 less than self. Not D (with 11) as 2x3x5x7x11 is not 210.

— Britten Mathematics (@BBMaMaths) February 27, 2018