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:

Answer:
30e-0.12t
40e-0.18t
Step-by-step explanation:
Amount of tax paid = 43-40 = 3
Tax rate = 3/40 = 0.75
0.75 x 100 = 7.5%
Tax rate = 7.5%
Answer:
Easy it's a right hand child
Step-by-step explanation:
Because if both husband and wife both have right hands. And it's 10% chance the child will be left handed. Then it's possible that the child is going to be a right hand.