The ms jodi has 950 non fiction books. 40% of those books are about science topics and 30% are about history. how many books are about other subjects?

285 (or 30% of 950)

Step-by-step explanation:

It might help if you think of it in terms of 10% and 1%.  10% is the same as dividing by 10. so 10% of 45 is 45.  1% is dividing by 100, so 10% of 55 is .55

Now, it also asks what is the amount that don't fir into the 30% and 40% of the books we know.  Well, that means we want to know the remaining 30%.  It's 30% history, 40% science and 30% other to make 100%.

So what is 30% of 950?  You could just multiply 950 by 30% or .3, or you could do the method I mentioned.  What is 10%?  95.  Then you multiply that by 3 to get 30%.  so 30% of 950 is 285

the answer is d

hope this