$a)\\\\
a_{n+1}-a_n=d\\
for\ n=1\\
a_2-a_1=d\\
d=3-1=2\ - difference\ between\ two\ consecutive\ terms\\\\
b)\\
a_n=a_1+(n-1)d\\
n=101\\
a_{101}=1+(101-1)*2\\
a_{101}=1+100*2=200+1=201\\\\
c)\\
Sn=\frac{a_1+a_n}{2}*n\\
n=20\\
a_n=a_{20}=1+(20-1)*2=1+38=39\\
Sn=\frac{1+39}{2}*20=400\ \ Sum\ of\ the\ first\ 20 \ numbers.$

6 0

3 years ago

Consider the sequence whose first five terms are shown. -59 ,-67 ,-65 ,-53 ,-31 ,... The first term is ____ To calculate the sec

GaryK [48]

Step-by-step explanation:

The sequence is as follows :

-59 ,-67 ,-65 ,-53 ,-31 ,...

The first term = -59

The second term = -67

Common difference = second term - first term

$=-67-(-59)\\\\=-8$

To calculate the second term add (-8).

To calculate each additional term, increase the amount added by -8.

7 0

3 years ago

In his last football game, Sean rushed for 94 yards. if his season total is now 871 yards, how many total yards did he have prio

Masteriza [31]

it should be somewhere around 110 to 120 yards

4 0

4 years ago

Find four consecutive even integers such that if the sum of the first and third is multiplied

Alenkasestr [34]

Answer:

Step-by-step explanation:

-8-10,-12-14

-8 plus -12 is -20

-20 times 5 is -100

-14 times 8 is -112

-100 is 12 more than -112

6 0

3 years ago