A cross-country skier covered 1/3 of her race in one hour, 2/5 of the race during the next hour, and the remainder of her race in the third hour. What fraction of the race did the skier cover during her third hour?

Respuesta :

the answer is 4/15. 1/3 + 2/5 = 11/15 Because 1/3 is equivalent to 5/15 and 2/5 is equivalent to 6/15. 5/15 + 6/15 = 11/15. 15/15 - 11/15= 4/15
Let x be the last portion,

The total distance he run : 1/3 + 2/5 + x = 1


x= 1- (1/3+2/5) ==> Reduce to the same denominator:

& you will find x=4/5