175 mL at 25% concentration of alcohol contains 0.25 (175 mL) = 43.75 mL of alcohol. If <em>v</em> is the amount of the 70% solution that you use, then that amount contains 0.7<em>v</em> mL of alcohol.
Mixing these two yields a total volume of 175 mL + <em>v</em>, and it contains 43.75 mL + 0.7<em>v</em> alcohol. You want to end up with a concentration of 45%, which means the ratio of the amount of alcohol to the total volume needs to be 0.45:
(43.75 mL + 0.7<em>v</em>) / (175 mL + <em>v</em>) = 0.45
Solve for <em>v</em> :
43.75 mL + 0.7<em>v</em> = 0.45 (175 mL + <em>v</em>)
43.75 mL + 0.7<em>v</em> = 78.75 mL + 0.45<em>v</em>
0.25<em>v</em> = 35 mL
<em>v</em> = 140 mL
Answer:
Step-by-step explanation:
40*25= 1000
1000-50-264=686
(y + z2) * x
(5 + 3(2)) * 2
(5 + 6) * 2
11 * 2
Your answer is 22
Exterior angle = 360/25 = 14.4 degrees
internal angle = 180-14.4 = 165.6 degrees
sum of all the angles = 165.6*25 = 4140 degrees answer
Answer:
Maria did her job properly. Both gears are perpendicular.
Step-by-step explanation:
Recall that given vectors a and b, they are perpendicular if and only if 
=0. If 
. Then 
.
IN our case a=(5,-1,2) and b) (1,-3,-4). So,
So both gears are perpendicular.
