Answer:
c
Step-by-step explanation:
I cant really see it can u type the equation?
We have that
<span>n (n-1) -4
for n=1
a1=1*(1-1)-4------> a1=-4
for n=2
</span>a2=2*(2-1)-4------> a2=-2
for n=3
a3=3*(3-1)-4------> a3=2
for n=4
a4=4*(4-1)-4------> a4=8
the answer is
-4,-2, 2, 8
Two cheaper books = x
more expensive = 1.5x
so, 2.5x=150
150/2.5=x=60
therefore the more expensive book = 90
