Answer:
those are both correct the awnser thar you have put.
the first question asks what is write the sum as a unit fraction. the unit fraction is 1/10 because it is how you show any unti fraction like 1/20 or 1/100. and 1/10+1/10+1/10=3/10 and is using unit fractions.
the second question is correct because the picture shows you that they start out with 3/5 because they are highlighted green. and they cross out 2 1/5 or 2/5. that is why 3/5-2/5=1/5
Hope this helps!