A chemist has 10% and 40% solutions of acid available. How many liters of each solution should be mixed to obtain 120 liters of 15% acid solution?

100 liters of  10% solution is used and 20 liters of  40% solution is used

Step-by-step explanation:

Let "X" amount of 10% solution is used. Then the amount of 40% solution used is equal to 120-X

Now

10% of X + 40% of (120-X) = 15% of 120

On solving the above equation, we get

liters

Amount of 40% solution used  = 120 -X = 120-100 = 20 liters

100 liters of  10% solution is used and 20 liters of  40% solution is used

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.