Answer:
It B ok
Step-by-step explanation:
Given:
Jeffery babysits for 4 dollars per hour and works as a math tutor for 7 dollars per hour.
He is only allowed to work 13 hours total per week.
He wants to make at least 65 dollars.
To find:
The system of inequalities to represent this situation.
Solution:
Let x be the number of hours he babysits per week and y be the number of hours h works as a math tutor.
He is only allowed to work 13 hours total per week. It means sum of x and y must be less than or equal to 13.

He wants to make at least 65 dollars. It means total earnings must be greater than or equal to 65.

Number of hours can not be negative.
.
Therefore, the required system of inequalities contains some equations,
and
.
<u>First let's calculate the exponents.</u>

<u>Now we should multiply and divide.</u>
<u />
<u />
<u>Now we should add and subtract.</u>
<u />
<u />
<u>Convert the improper fractions into mixed numbers.</u>
<u />
<u />
<u />
<u>Answer : </u>
<u />
<u />
<u />
Answer:
4 mph
Step-by-step explanation:
The average speed of an object is given by the total distance covered by the time taken:

where
d is the total distance covered
t is the time taken
in the first part, the person runs for 0.4 hours at a speed of 7 mph, so the distance covered in the 1st part is

Then the distance covered in the second part is
, so the total distance is
(1)
The total time elapsed is 0.4 hours (first part) + 0.8 hours (second part), so

So we can write the average speed as
(1)
We want the average speed to be 5 mph,
v = 5 mph
Therefore we can rearrange eq.(1) to find d2:

And therefore, the speed in the second part must be
