Question

Martha exprime 5 naranjas para hacer jugo. Si ya tiene 3/5 litros de jugo, ?Cuanto le falta para llenar un recipiente que tiene 9/10 de capacidad?

Answer 1

Martha squeezes 5 oranges to make juice. If she already has 3/5 liters of juice, how many times does she need to fill a container that has 9/10 capacity?

According to the problem, with 5 oranges Martha has
`(3)/(5)` litters of orange juice.

First we have to find how many litters are needed to reach the
`(9)/(10)` litters capacity of the container. This can be mathematically expressed as follows:

`(3)/(5)L+X=(9)/(10)L`

Let’s find X:

`X=(9)/(10)L-(3)/(5)L`

`X=(3)/(10)L`

This means that Martha needs
`(3)/(10)L` to reach the
`(9)/(10)L` capacity.

Now, if 5 oranges represent
`(3)/(5)L`, how many oranges represent
`(3)/(10)L`?

This can be solved by “the rule of three” also called cross-multiplication:

5 oranges--------
`(3)/(5)L`

N oranges--------
`(3)/(10)L`

`N=((3)/(10)L(5))/((3)/(5)L)`

`N=(5)/(2)oranges`

This is equivalent to
`2.5 oranges`

This means Martha needs 2.5 oranges or
`(3)/(10)L` to to fill a container that has 9/10 capacity.