N(-5/8)=-0.4
times both sides by -8/5
n(-40/-40)=3.2/5
n1=0.64
n=0.64
If we assume that
x isthe number of multiple choice questions, and y is the number of word problems, we can write a system of equations like:
{ x + y = 38
{ 2x + 5y = 100
If we multiply the first equation by -2 we get:
{ -2x-2y = -76
{ 2x + 5y = 100
Now if we add both equations we get only equation with 1 unknown (y) :
3y = 24 ⇒ y = 8
Substituting the calculated value to the first equation we get:
x + 8 = 38 ⇒ x = 30
The solution:
{ x = 30
{ y = 8
means that:
The test had 30 multiple choice questions, and 8 word problems.
Answer:
Except 4 out of 6
the answer is the third one
Even numbers end with 2,4,6,8, or 0. Thus, 28 is the even number.
