Question

Determine which of the following numbers are divisible by $5$ and by $10.$
$25,125,250,1250,10205,70985,45880$
Check whether the numbers that are divisible by $10$ are also divisible by $2$ and $5.$

Answer 1

We know that

If the unit digit of a number is $5$ or $0$, it is divisible by $5$

If the unit digit of a number is $0$, it is divisible by $10$

If the unit digit of a number is an even number, it is divisible by $2$

Now, investigate for the given numbers.

$25=$ Here, unit digit is $5$, so it is divisible by $5$ only

$225=$ Here, unit digit is $5$, so it is divisible by $5$ only

$250=$ Here, the unit digit is $0$, so the number is divisible by $5,10$ and $2$

$1250=$ Here, the unit digit is $0$, so the number is divisible by $5,10$ and $2$

$10205=$ Here, unit digit is $5$, so it is divisible by $5$ only

$70985=$ Here, unit digit is $5$, so it is divisible by $5$ only

$45880=$ Here, the unit digit is $0$, so the number is divisible by $5,10$ and $2$