Answer:
The number of students that bring their lunches is 12
Step-by-step explanation:
Let
x -----> the number of students that bring their lunches
y -----> the total number of students in a class
we know that
The number of students that bring their lunches divided by the total number of students in a class must be equal to 3/8
-----> equation A
-----> equation B
substitute the value of y in equation A and solve for x
therefore
The number of students that bring their lunches is 12
We are looking for a new number which is 30 less than 10. We will get the new number by subtracting 30 from 10. We write it down as: 10-30=-20
And finally the solution for: What number is 30 less than 10? is -20
Hope this helps!!
Superman is 100 mph
Desperado is 80 mph
there total speed is 180 mph and Superman is 20 mph faster