Question

Lucille has an aquarium with 9 gallons of water which weighs 85 pounds. The stand holding the aquarium can hold no more than 112 pounds. She wants to add 2.5-pound rocks, r, her tank. Complete the inequality to show how many rocks she can add. R≤

Answer 1

`r\leq 10.8`

OR

`r\leq 10`

Explanation:

Given that:

Amount of water in the aquarium = 9 gallons

Weight of water in the aquarium = 85 pounds

Total weight that aquarium can hold = 112 pounds

Weight of each rock = 2.5 pounds

To find:

The inequality to find the number of rocks,
`r` that can put in her tank.

Solution:

First of all, let us find more weight that the aquarium can hold after putting the water in the aquarium.

Additional weight that can be put in the aquarium = Total weight - Weight of water = 112 - 85 = 27 pounds

This 27 pounds can be of rocks.

Let the number of rocks that can be put in the aquarium =
`r`

Total weight of
`r` number of rocks = Weight of one rock multiplied by
`r`=2.5
`r`

Now, this weight of rocks must be lesser than or equal to 27 pounds.

Therefore, the in equality is:

`2.5r\leq =27\\\Rightarrow r \leq 10.8\\OR\\\Rightarrow r \leq 10`