Question

A glass is
1
3
full. Then 40cm3 of orange juice is poured in.
The glass is now
5
7
full. What is the total volume of the glass?

Answer 1

Answer:  The required total volume of the glass is 105 cm³.

Step-by-step explanation:  Given that a glass is $\dfrac{1}{3}$ full. After pouring 40 cm³ of orange juice in the glass, it became $\dfrac{5}{7}$ full.

We are to find the total volume of the glass.

Let x cm³  represents the total volume of the glass.

Then, according to the given information, we have

$\dfrac{1}{3}x+40=\dfrac{5}{7}x\\\\\\\Rightarrow \dfrac{5}{7}x-\dfrac{1}{3}x=40\\\\\\\Rightarrow \dfrac{15-7}{21}x=40\\\\\\\Rightarrow \dfrac{8}{21}x=40\\\\\\\Rightarrow x=\dfrac{40\times21}{8}\\\\\Rightarrow x=105.$

Thus, the required total volume of the glass is 105 cm³.