b. 450.80
you multiply 40 x 9.80 ...equals 392.
<span>take 1/2 of 9.80...that equals 4.90. </span>
<span>4.90 plus 9.80 equals $14.70 x 4 = 58.80 </span>
<span>$58.80 plus 392. equals $450.80</span>
+ is positive, or plus
- is negative, or minus
the third one is multiply, can look like * and "x"
the fourth one is divide, can look like "/"
hope this helps
5x=25 X= 5
X/3=7 X= 21
2x=14 X= 7
x/2=12 X=6
x/4=6 X=24
The sequence is an geometric progression;
Nth=a₁r^(n-1)
a₁ is the first term=-1
r=ratio=a₂/a₁=6/-1=-6
Nth=-1(-6^(n-1)
NTh=an
a₁=-1(-6⁰)=-1
a₂=-1(-6¹)=6
a₃=-1(-6²)=-36
a₄=-1(-6³)=216
therefore this serie is rising at an increasing fast speed, it is an geometric progression.