1.
If
y
varies inversely as
x
and
y
= 12 when
x
= 7, find
x
when
y
= 2.
A.
7
B.
10
C.
5
D.
42
Hint
2.
Suppose
y
varies directly as
x
and
y
= 13 when
x
= 7. Find the constant of variation and write an equation.
A.
k
=
and
y
=
x
B.
k
=
and
y
= 13 · 7
x
C.
k
=
and
y
=
x
D.
k
=
and
y
= 13 · 7
x
Hint
3.
Use
y
=
to find the value of
y
when
x
= 14.
A.
56
B.
8
C.
98
D.
28
Hint
4.
If
y
varies inversely as the cube of
x
and
y
= 8 when
x
= 2, find
x
when
y
= 1.
A.
x
= 1
B.
x
= 8
C.
x
= 2
D.
x
= 4
Hint
5.
Dakota wants to cook a meal for his family. He knows that the more people who help, the less time it will take to prepare the food. Write an equation that represents this situation. Let
C
be the cooks in the kitchen,
T
be the time and
k
as the constant of variation.
A.
k
=
C
T
B.
k
=
CT
C.
T
=
kC
D.
C
=
kT
Hint