15 x 25 = 375
15 x 50 = 750
375 + 750 = 1,125
She has 1,125 books.
Ratio in which 180 should be divided is 4:5:9
firstly we need to find the total number of portions
this we can find by adding all the numbers making up the ratio
4 + 5 + 9 = 18
180 is made of 18 portions
size of 1 portion = 180 / 18 = 10
when dividing 180 into the respective ratio 4:5:9 the portions are as follows
4 x 10 = 40
5 x 10 = 50
9 x 10 = 90
therefore when we divide 180 in the ratio 4:5:9
the answer we get is
40 :50: 90
They give us the length of side of the square which is 3-7x.
To get an expression for the perimeter that is expressed as a product we have to multiply the expression 3-7x by four since every square has four sides. This will give us an expression of 4(3-7x). We than can use the distributive property to multiply everything inside the parenthesis by 4. This will give us an expression of 12-28x.
The answer is B. Sorry if I'm wrong.
I think we have found them and cared for them I don't think it's right b/c I guessed.