Answer:
15.

16. 10 ml of 20% saline and 40 ml of 10% saline
Step-by-step explanation:
A chemist takes x ml of 20% saline and y ml of 10% saline. In total, he takes
x + y ml that is 50 ml, so

There are
ml of salt in x ml of 20% saline and
ml of salt in 10% saline. There are
ml of salt in 50 ml of 12% saline. Thus,

15. We get the system of two equations:

16. Solve this system. From the first equation:

Substitute it into the second equation:

Step-by-step explanation:
98 = 188t - 16t^2
-16t^2 + 188t = 98
-16t^2 + 188t - 98 = 0
8t^2 - 94t + 49 = 0
Use the quadratic formula with a = 8 , b = -94 , c = 49 to get the solutions
t = [(47 - root 1817) / 8]≈ 0.55
and
t = [(47 + root 1817) / 8] ≈ 11.20
Answer:
Step-by-step explanation:
In March, Your Co. will collect 20% of January's sales, 30% of February's sales, and 50% of March's sales:
.20×50 +.30×40 +.50×60 = 10 +12 +30 = 52
Similarly, in April, collections will be ...
.20×40 + .30×60 + .50×30 = 8 +18 +15 = 41
Answer:
x= - 9/28 ± √60/7
Step-by-step explanation:
Answer:
B.
Step-by-step explanation:
B. 0.078 is your answer