# Solutions to Problem Set 21

Math 101-06

11-1-2017

[Variation]

1. y is directly proportional to x.

Suppose that when .

Find y when . Give an exact answer.

y varies directly with x:

when :

Hence,

Set :

2. y varies directly with x.

Suppose that when .

Find x when . Give an exact answer.

y varies directly with x:

when :

Hence,

Set and solve for x:

3. y is inversely proportional to x.

Suppose that when .

Find y when . Give an exact answer.

y is inversely proportional to x:

when :

Hence,

Set :

4. y is inversely proportional to x.

Suppose that when .

Find x when . Give an exact answer.

y is inversely proportional to x:

when :

Hence,

Set and solve for x:

5. y varies directly with .

Suppose that when .

Find y when . Give an exact answer.

y varies directly with :

when :

Hence,

Set :

6. w is directly proportional to x and inversely proportional to y.

Suppose when and .

Find w when and . Give an exact answer.

w is directly proportional to x and inversely proportional to y:

when and :

Hence,

Set and :

Without work, all life goes rotten. But when work is soulless, life stifles and dies. - Albert Camus

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