9514 1404 393
Answer:
- 100 mL of 75% solution
- 150 mL of pure alcohol
Step-by-step explanation:
Let x represent the quantity (in mL) of pure alcohol needed for the mix. Then the amount of 75% needed is (250-x). The amount of alcohol in the mixture is ...
1.00x +0.75(250 -x) = 0.90(250)
0.25x +187.5 = 225 . . simplify
0.25x = 37.5 . . . . . . . . subtract 187.5
x = 150 . . . . . . . . . . . . . divide by 0.25
(250 -x) = 100 . . . . mL of 75% solution
You need 100 mL of the 75% solution and 150 mL of pure alcohol to obtain the desired mixture.
Answer:
uhmm...
Step-by-step explanation:
Answer: 105 of them are hummingbirds.
Step-by-step explanation:
I there are a total of 350 birds then 30% o 350 will give the number o hummingbirds.
350 of 30%
350 * 0.3 = 105
This is the concept of geometry, we are required to find the values of angle a,b,c,d;
Given that the triangles are by line intersecting two parallel lines, therefore we can conclude that both triangles are similar;
thus;
angle b=40° ⇒alternate angles
angle b= angle c=40° ⇒base angles of isosceles triangles are equal;
angle d=180-(40+40)=180-80=100°
angle a=360-80=240°