Answer:
This sum is the sum of an arithmetic sequence. There is a formula for the sum of an arithmetic sequence which can be looked up or derived by a variety of means.
A nice approach for this sequence is the following. Notice that the sum of first and last number in the sequence is the same as the sum of the second and second last, and also the same as the sum of the third and third last, and so on.
There are n of these pairs. So the desired sum is n x (first number + last number). But the first number is 1 and the last on is 2n. Thus the desired sum is n(1 + 2n).
Hope this helps!!
Mark Brainleast!!!!!!!!!!!
Answer:
8
Step-by-step explanation:
Hope it helps
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Can i have brainly pls
Answer:
Each friend got 2 apples
Step-by-step explanation:
[original amount of apples]-[Apples Sally has after distribution] = [friends] x [number of apples]
Filling in the brackets, you get this equation.
15-9=3 x apples per friend
6=3 x apples per friend
2 = apples per friend
Answer:
Option D is the correct answer.
Explanation:
A girl has 3 different swimsuits, 4 different shorts and 3 different pairs of flip-flops.
Different ways can this girl wear a swimsuit, a pair of short and a pair of flip-flops = 3P₁ x 4P₁ x 3P₁
= 3 x 4 x 3
= 36
Different ways can this girl wear a swimsuit, a pair of short and a pair of flip-flops = 36
Option D is the correct answer.
