10=5*2
9= 3*3
8= 2*2*2
7= 7
6= 3*2
5= 5
4= 2*2
3= 3
2= 2
1= 1
We need a product that include all of the combinations in the right column.
Starting from the top:
10 gives us: 5*2
9 gives us: 3*3
8 gives us: 2*2 (we already have the third 2)
7 gives us: 7
6 gives us: nothing (we already have both a 2 and a 3)
5 gives us: nothing
4 gives us: nothing
3 gives us: nothing
2 gives us: nothing
1 gives us: 1 So: 5*2*3*3*2*2*7*1=2520. There is no number between 1 and 2000 that fits.
48 has the most factors; it has 10 factors: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48
The number 10 can be the product of 2 and 5, 1 and 10. This means that 10 has 4 factors. :]
11
A multiple is found by multiplying the number. Whereas a factor is what the number can be divided by. For example - multiples of 10 are; 10, 20, 30, 40, ... Factors of 10 are; 1, 2, 5, 10
Four
2555
12
48 has 10 factors.
The numbers between 10 and 30 that have exactly 5 factors are 16 and 25. The number 16 has factors 1, 2, 4, 8, and 16. The number 25 has factors 1, 5, 25, but since it is a perfect square, it also includes the repeated factor of 5. These are the only two numbers between 10 and 30 that have exactly 5 factors.
5, 10, 15 and 20 have five as a factor. The number 16 has five factors.
3 x 4 = 12
16, with factors 1, 2, 4, 8 and 16.
There are no factors of 10 between 20 and 100.
6, 8, 10, 14, 15
48 has the most factors; it has 10 factors: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48
Oh, isn't that a happy little question! Let's see here... To find the multiples of 10 between 2000 and 5000, we simply need to divide the endpoints by 10. When we do that, we get 200 and 500. So, there are 500 - 200 - 1 = 299 multiples of 10 between 2000 and 5000. Isn't that just delightful?
Subtraction of 10 from 2000 gives the required number. 2000 - 10 = 1990 is 10 less than 2000.