Question

check whether the following numbers are divisible by 4 18 or not 19800 and explain this not come to me
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Answer 1

Divisibility Test for 4 : If the No. formed by Last two digits is divisible by 4, then the given no. will be divisible by 4.

Divisibility Test for 18 : For a no. to be divisible by 18, it should be separately divisible by both 2 and 9.

Divisibility Test for 2 : Unit place digit should be 0, 2, 4, 6 or 8.

Divisibility Test for 9 : Sum of the did of the given no. should be divisible by 9.

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Now, Let's test the no. 19800:

1) Last two digit numbers are: 00.

and (00/4=0) i.e. divisible by 4..

So, 19800 is divisible by 4.

2) Units Place digit is 0.. So, no. is divisible by 2

Sum of digits is : 1+9+8+0+0 = 18.. which is divisible by 9 = 18/9 = 2.. So, no. is divisible by 9.

Now, since no. of divisible by both 2 and 9.. It is divisible by 18