Acone has a volume of 7,560 cubic millimeters. what is the volume of a similar cone that is one sixth the size of this cone?

Solution:

Let "x" be the number of hot dogs sold

Let "y" be the number of sodas sold

Each hot dog costs $1.50 and each soda costs $0.50

You sold a total of 87 hot dogs  and sodas combined

Therefore,

x + y = 87

y = 87 - x eqn 1

At the  end of the night you made a total of $78.50

Therefore,

1.50x + 0.50y = 78.50 eqn 2

Substitute eqn 1 in eqn 2

1.5x + 0.5(87 - x) = 78.5

1.5x + 43.5 - 0.5x = 78.5

x = 78.5 - 43.5

x = 35

Substitute x = 35 in eqn 1

y = 87 - 35

y = 52

Thus 35 hot dogs and 52 sodas were sold