Question

Which number is divisible by 3 and 5?

A. 130
B.325
C.4,113
D.2,040

Answer 1

if its divisible by 3, then the sum of its digits is divisible by 3

if its divisible by 5, then the last digit is 0 or 5

Answer 2

I don't understand. Please explain?

Answer 3

take the first one
130
it is divisible by 5, because the last digit is 0, but if you add 1+3=4 is not divisible by 3 so the number is also not

for
325
again its divisible by 5, but 3+2+5 = 10 is not divisible by 3 so neither is the number

for
4113
this is not divisible by 5 because the last digit is NOT 0 or 5, its 3

for
2040
this is divisible by 5, and 2+0+4+0 = 6 is divisible by 3, so 2040 is divisible by 3 and 5

Answer 4

is 3123420 divisible by 5 and 3?

Answer 5

no.