Answer:
80
Step-by-step explanation:
10 limits it to 50, 60, 70, 80, and 90
2 eliminates none since 50=25, 60=30, 70=35, 80=40 and 90=45
8 divided by each number only leaves one option of 80. (80/8= 10) (80/10=8) (80/2=40)
42
Hope this helps
yes
23 x^ 4 y^ 7
48
add the values of the ages of the lecturers which should give you 434 then divide by the number of lecturers in question
=480/10
=48