A glass is 4 7 full. Then 70cm3 of orange juice is poured in. The glass is now 3 4 full. What is the total volume of the glass

Question

 i need help please help with this question

 

Answer 1

4/7V + 70 = 3/4V

 

70 = 3/4V - 4/7V

 

70 = 21/28V - 16/28V

 

70 = 5/28V

 

V = 70*28/5 = 392

 

Check:

 

  4/7 of 392 = 224

  224 + 70 = 294

  294/392 = 0.75 = 75% = 3/4

 

The volume of the glass is 392