Question

A birdbath is filled to the top. Tuesday, the water decreases by 7/8 cup. On Wednesday, the amount decreases by 3/4 cup. Find the total change in the volume of the water in the bowl after two days. Then decide is the number positive or negative

Answer 1

Answer: The total change in the volume of the water in the bowl after two days is decreased by
`(13)/(8)`

And the number must be negative as it is decreased by this amount.i.e.

`(-13)/(8)\ cups`

Explanation:

Since we have given that

Let the amount of water be 'x'.

On Tuesday, the water level decreases by
`(7)/(8)\ cup`

So, it becomes,

`x-(7)/(8)`

On Wednesday, the water level decreases by
`(3)/(4)\ cup`

So, it becomes,

`x-(7)/(8)-(3)/(4)\\\\=x+(-7-6)/(8)\\\\=x-(13)/(8)`

Hence, the total change in the volume of the water in the bowl after two days is decreased by
`(13)/(8)`

And the number must be negative as it is decreased by this amount.i.e.

`(-13)/(8)\ cups`