The ratio of the number of mystery books to the number of science fiction books is 4: 3. the ratio of the number of science fiction books to the number of biographies is 4: 5. if there are 48 science fiction books, find the total number of books.

Given is the number of science fiction books = 48

Let the number of mystery books be = x

Let the number of biographies be = y

Ratio of the number of mystery books to the number of science fiction books is 4:3 so

=

Ratio of the number of science fiction books to the number of biographies is 4:5 so

=

Hence there are 48 science fiction books, 64 mystery books and 60 biographies.

So total number of books are =

solution:

we have to construct

∠m nt ≅ ∠p qr

the steps to draw this construction are

step 1: use a compass to draw an arc from point q which intersects the side pq at point a and the side qr at point b.

step 2: draw a segment nt and use the same width of the compass to draw an arc from point n which intersects the segment nt at a point x.

step 3:

step 4: join points n and y using a straightedge.

step 3:

option (d).maintaining the same width of the compass as ab, draw an arc from point x such that it intersects the arc drawn from n in a point y.

to draw   congruent angles , 1. width of compasses while drawing two angles should be same i.e from point at which angle has to be drawn, 2.the distance between the two points where the compass intersects the two sides should be same while drawing any two congruent angles.

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15