Question 903706:  mother painted 2/5 of a wall white and 3/10 of it blue.
 
a, what fraction of the wall did she paint in all?
 
b, what fraction of the wall had she still to paint? 
 Answer by Theo(13342)      (Show Source): 
You can  put this solution on YOUR website! in order to add fractions together, you need to get a common denominator.
 
 
your denominators are 5 and 10.
 
 
multiples of 5 are 5,10,15,20,... 
multiples of 10 are 10,20,30,...
 
 
it appears that 10 is the least common multiple ot 5 and 10, so we'll use that.
 
 
2/5 * 2/2 = 4/10
 
 
now you can add the fractions together because they have a common denominator.
 
 
4/10 + 3/10 = 7/10
 
 
she painted 7/10 of the wall in total.
 
 
she still needs to paint 1 - 7/10 of the wall.
 
 
once again, you need common denominators.
 
 
1 * 10/10 = 10/10
 
 
the equation becomes:
 
 
10/10 - 7/10 = 3/10 of the wall that still needs to be painted.
 
 
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