Noel has 5/6 of a yard of purple ribbon and 9/10 of a yard of pink ribbon. how much ribbon does she have altogether?

You get 14/16 and when you simply you then get 7/8.

To do this, you will want to make both of the denominators common or in other words, the same. The easiest way is to multiply the denominators together.
(5*10)/(6*10) and (9*6)/(10*6)
50/60 and 54/60
Add these together and you get 104/60 which is equal to 1.7333... yards of ribbon.

Hope I helped!

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