First, we need to find out how many houses that Hannah received money from. We can do this by dividing the total amount of money she received by the amount she received per house.
780 / 5 = 156
Hannah received money from 156 houses.
To find the amount of houses she did NOT collect money from, we just need to subtract the amount of houses that she DID receive money from away from the total amount of houses in her neighborhood.
278 - 156 = 122
Hannah did not collect money from 122 houses.
Hope this helped! =)
bearing in mind that an explicit form is simply the sequence written as a function of some variables, so we simply simplify and add like-terms.

Answer:
6.7-(-2.5)=9.2 6.7+(-2.5)=4.2 Neither
2.5 + 6.7 6.7 - 2.5 2.5 - 6.7
-2.5 + 6.7 -2.5 - 6.7
-6.7 + 2.5
If i were you, I would just plug these into my calculator.
1. 1.587
2. 11.469
3. 6.503
4. 1.81
5. 28.984