1.
If
y
varies directly as the cube of
x
and
y
= 30 when
x
= 2, find
x
when
y
= 468.75.
A.
7
B.
9
C.
5
D.
3
Hint
2.
If
y
varies inversely as
x
and
y
= 12 when
x
= 7, find
x
when
y
= 2.
A.
7
B.
5
C.
10
D.
42
Hint
3.
If
y
varies directly as the square root of
x
and
x
= 25 when
y
= -15, find
x
when
y
= -108.
A.
x
= -5
B.
x
= 1500
C.
x
= 4500
D.
x
= 6
Hint
4.
If
y
varies inversely as the cube of
x
and
y
= 8 when
x
= 2, find
x
when
y
= 1.
A.
x
= 2
B.
x
= 8
C.
x
= 4
D.
x
= 1
Hint
5.
If
y
varies jointly as
x
and the cube root of
z
,
and
y
= 30 when
x
= -5
and
z
= 27, find y when
z
= -8 and
x
= 0.5.
A.
y
= 2
B.
y
= -2
C.
y
= 4
D.
y
= 20
Hint