Question

Question #3dc62

Answer 1

`"elliptical"=16 " "` and `" ""treadmill"=32`

Explanation:

Let `l` be the number of minutes you spend on the elliptical, and `t` be the number of minutes you spend on the treadmill.

We can make 2 equations:

We know that the total number of minutes is 48, so:

`l + t = 48`

We know that the total calorie burn must be 400, so:

`9l + 8t = 400`

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Now that we have a system of equations, we can solve it through subtraction, like this:

Multiply both sides of the first equation by `8`:

`8l + 8t = 384`

Now subtract this modified form of the first equation from the second equation:

`color(white)"X.." 9l + 8t = 400`
`-(8l + 8t = 384)`
`-------`

`color(white)"XXXXX"l = 16`

So we know what `l` is. To find what `t` is, we need to plug `l` back into one of the equations and solve for `t`:

`l + t = 48`

`16 + t = 48`

`t = 32`

So `l=16` and `t=32`.

Final Answer