Example (continue)

Hello everyone...welcome again...like i said at the last post. I'll give another examples about the topic that will we discuss which is Arithmetic Progression (A.P).

 Now,I'll continue with example number 2 which is using sum formula. Okay..here we go...
In this example, I'll explain step by step.

Example 2

Given the following numbers :

3,6,9,12,15....

Question : Calculate the Sum of the series until the 63rd term.

Note:

In this question, the question ask to calculate the Sum of the series until the 63rd term. So that mean, we need to find the Sum until 63rd term.

Formula the we will use is

Sn = n [2a + (n-1)d]
        2

Sn = Sum
a    = the first term ............................................. 3                                                            
n   = until which sum we need to find ............... 63
d   = the difference between the number ........... 3 (6-3)

Step 1

Input all the information above into the formula.

Sn = n [2a + (n-1)d]
        2
S63 = 63[2(3) + (63-1)3]
           2
Step 2

Divide 63,multiply 2 and 3 then multiply 63 with 3
            2
S63 = 31.5 [(2x3) + (62)x3]

Step 3

Then, plus the answer 2 x 3 and answer 62 x 3

S63 = 31.5 [(2x3) + (62)x3]
       = 31.5 [6 + 186]

Step 4

After that, multiply the answer 63 divide by 2 and the answer 2 x 3 and answer 62 x 3.

S63 = 31.5 [6 + 186]
       = 31.5 [192]

Step 5

Lastly,multiply the answer of 63 divide by 2 and the answer of 6 + 186.

S63 = 31.5 [6 + 186]
       = 31.5 [192]

       = 6048

Then, the sum of the series until 63rd term is 6048.


Easy right...