Question

THE SUM OF EVEN NUMBERS BETWEEN 1 TO 31
please reply quickly

Answer 1

if you need it fast, get a calculator and add them up

Answer 2

what does an even number look like in general?

Answer 3

smooth

Answer 4

good morning! looks like things have speeded up a bit here

Answer 5

morning :) and yeah, but i just got an aw snap page nonetheless:/

Answer 6

even numbers are generally of the form: 2n
2(1) = 2
2(15) = 30

\[\sum_{n=1}^{15}2n\]
\[2\sum_{n=1}^{15}n\]

Answer 7

this is an example of arithmetic progression , so how can i solve it using the formula ?

Answer 8

which formula?

Answer 9

2+4+6+8+... common difference of 2

an = a1 + d(n-1)

an = 2 + 2(n-1)

an = 2(1+n-1)

an = 2n ; which gets us to the general form of an even number

Sn = n(a1+an)/2

Sn = n(2+2n)/2

Sn = 2n(1+n)/2

Sn = n(1+n)

Answer 10

thank u , i got the key to get an answer ....
can i ask another question that i realy cant understand
thank....

Answer 11

please help me to solve this equation n/2[2a+(n-1)d]=1800
where a=6,d=6,Sn=1800

Answer 12

\[ \frac n2(2a+(n-1)d)=S_n\]
where a=6,d=6,Sn=1800
just replace the letters with the given values
\[ \frac n2(2(6)+(n-1)6)=1800\]
\[ \frac n2(12+6n-6)=1800\]
\[ \frac n2(6+6n)=1800\]
\[ \frac n26(1+n)=1800\]
\[ 3n(1+n)=1800\]and solve for n