Let x=gallons of 80% solution to be mixed
x+80=gallons go final 70% mixture
..
80%*x+30%*80=70%*(x+80)
.8x+24=.7x+56
.1x=32
x=320
gallons of 80% solution to be mixed=320
Answer:
He needs 7 more consecutive successful first serves to raise his first serve percentage to 60%.
Step-by-step explanation:
After n consecutive serves, his total number of serves is going to be n+8, since he has already served 8 times. In the best case, his number of successful first serves is n+2.
His percentage of succesful first serves is the division of the number of succesful first serves divided by the total number of serves. So

We want
. So







He needs 7 more consecutive successful first serves to raise his first serve percentage to 60%.
Let Ch and C denote the events of a student receiving an A in <u>ch</u>emistry or <u>c</u>alculus, respectively. We're given that
P(Ch) = 88/520
P(C) = 76/520
P(Ch and C) = 31/520
and we want to find P(Ch or C).
Using the inclusion/exclusion principle, we have
P(Ch or C) = P(Ch) + P(C) - P(Ch and C)
P(Ch or C) = 88/520 + 76/520 - 31/520
P(Ch or C) = 133/520
Answer:
Disagree
Step-by-step explanation:
Remember rotating 90 degrees means (y,-x)
A= (1,2)
A'= (2,-1)
So it is disagreed.
Hope this help :)
Answer:
Step-by-step explanation:
Let the original water level is x.
<u>Use below equation to find its value:</u>
- x + 2.4 + 3 1/2 = 162 + 14.6
- x + 2.4 + 3.5 = 176.6
- x + 5.9 = 176.6
- x = 176.6 - 5.9
- x = 170.7 cm