Respuesta :

i’m pretty sure it’s 20
  • We have first find out the factors of the numbers.
  • Factors of 15 are 1, 3, 5, 15.
  • Factors of 20 are 1, 2, 4, 5, 10, 20.
  • Factors of 21 are 1, 3, 7, 21.
  • Factors of 34 are 1, 2, 17, 34.
  • Therefore, there are no numbers in the list, which are divisible by 5, 10 and 15.
  • 15 can be divisible by 5 and 15 not 10.
  • 20 can be divisible by 5 and 10 not 15.

Hope you could get an idea from here.

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