BreBreDoeCCx BreBreDoeCCx

04-03-2018
Mathematics

contestada

Find S25 for (-7) + (-2) + 3 + 8 +...

A.
1,320

B.
1,325

C.
825

D.
820

Respuesta :

Banabanana Banabanana

04-03-2018

[tex]a_1=-7 \\ a_2=-2 \\ \\ d=a_2-a_1=-2-(-7)=5 \\ \\ \\ S_{25}= \cfrac{2(-7)+(25-1)5}{2}\cdot25 = \cfrac{-14+120}{2}\cdot25 =\cfrac{106}{2}\cdot25 =1325[/tex]

Your answer is B. 1325

Answer Link

Otras preguntas

Canada has a population that is about 1/10 as large as the United States. If Canada's population is about 32,000,000, about how many people live in the United S

K stands for a whole number. K + 7 is greater than 100 K - 7 is less than 90 Write all the numbers that k could be. Please help me

What unions were open to African Americans in the 1920s?

what is 16,700,000,000,000,000 estimated as the product of a single digit and a power of 10

Cory's average score after 8 tests is 91%. If he gets a 78% on his 9th test what will his new average be? How do i figure out this problem?

what are the similarities between insects and humans

Solve each compound Inequality. 42. -2 ≤ d + 1/2 < 4 1/2 44. 2t ≤ -4 or 7t ≥ 49 46. -1 ≤ a - 3 ≤ 2 48. A town's high temperature for a given month is 88 degr

Here is a sequence of shapes made from squares and circles. The sequence continues in the same way. The formula for the number of circles (c) in shape number (n

Select the product of (7x - 2)(7x + 7).

what is the theory that tax cuts can raise supply called