Answer:
Step-by-step explanation:
In order to write the series using the summation notation, first we need to find the nth term of the sequence formed. The sequence generated by the series is an arithmetic sequence as shown;
4, 8, 12, 16, 20...80
The nth term of an arithmetic sequence is expressed as Tn = a +(n-1)d
a is the first term = 4
d is the common difference = 21-8 = 8-4 = 4
n is the number of terms
On substituting, Tn = 4+(n-1)4
Tn = 4+4n-4
Tn = 4n
The nth term of the series is 4n.
Since the last term is 80, L = 4n
80 = 4n
n = 80/4
n = 20
This shows that the total number of terms in the sequence is 20
According to the series given 4 + 8 + 12 + 16 + 20+ . . . + 80
, we are to take the sum of the first 20terms of the sequence. Using summation notation;
4 + 8 + 12 + 16 + 20+ . . . + 80 =
The answer is a rational number is one integer divided by
another, and can be represented in either decimal of fraction form. The explanation
behind this is visualize you are using long division to divide one number by one
more. You divide, and then you acquire a remainder. Then you carry down a
zero (multiply by ten) and divide again. Well, there are only so many balances
you could perhaps have. For example, for 5, your choices are 0, 1, 2, 3,
and 4. Sooner or later, you will replicate a remainder, at which fact you
will just keep dividing the same method you did last time you saw that
remainder -- and that's the reason why it repeats.
Answer:
66 in.
Step-by-step explanation:
the rectangle has an area of 48in. because 4x11 = 48. The triangles have a base of 6 because 12 ÷ 2=6. the formula for area of a triangle is BxHx1/2 and the height is 3in so 6x3= 18 and 18x1/2=9 and there is two triangles and the other has the same area. Then you add up the area of everything so 48+9+9 = 66
72 is dividable by 3. It is divisible by 3 because when you add 7 and 2, you get 9. According to the tests for divisibility, if the sum of the digits is divisible by 3, then the whole number is. 9 is divisible by 3, therefore 72 is as well.