The correct options are
B b = a + 5
C c = b + 5
D a = c - 10
Let a, b and c be the three consecutive multiples of 5.
The consecutive multiples of '5' differ by 5.
So, the second multiple, b = a + 5,
and third multiple, c = b + 5
⇒ c = a + 5 + 5
⇒ c = a + 10
⇒ a = c - 10
∴ a + b + c = a + a + 5 + a + 10 ≠ 10
Therefore, options B, C and D are correct.