Answer:
A) 900
B) 5400
C) 3600
Step-by-step explanation:
A) Number of 4 digit multiples of 5:
(9999-1000+1)/5= 1800
[I added one to the 9999-1000 because it includes 9999]
Now, out of those 1800 numbers that are divisible by 5, 900 of them are even. (so they are divisible by 10 [or 5 and 2])
Therefore, the answer to A is 900
B) Number of 4 digit multiples of 2:
(9999-1000+1)/2= 4500
This means that there are 4500 even 4 digit numbers.
We have already figured out that there are 900 numbers that are divisible by both 5 and 2. 1800-900=900 4-digit numbers that are not divisible by 2, but are divisible by 5.
So if we add the 4500 (numbers that are divisible by 2) and the 900 (numbers that are only divisible by 5, but not 10), we get 5400.
C) There are 9999-1000+1= 9000 4-digit numbers. We know that there are 5400 numbers that are divisible by either 5 or 2, so 9000-5400=3600
Feel free to ask any questions! :)
