## anonymous one year ago Use the formula for the sum of the first n terms of a geometric sequence to solve. Find the sum of the first 8 terms of the geometric sequence: -8, -16, -32, -64, -128, . . . . A. -2003 B. -2040 C. -2060 D. -2038

1. anonymous

@Michele_Laino

2. anonymous

i thought it was b

3. Michele_Laino

the first term is: a1=-8, the constant is d=2 so the requested sum, is: $\Large {S_8} = {a_1}\frac{{1 - {q^8}}}{{1 - q}} = - 8 \cdot \frac{{1 - 256}}{{1 - 2}} = ...?$

4. anonymous

$r=\frac{ -16 }{ -8 }=2$

5. anonymous

i got the answer thnx for the help doe

6. anonymous

Find the probability. What is the probability that a card drawn from a deck of 52 cards is not a 10?

7. anonymous

i need help with this one though

8. anonymous

A. 12/13 B. 9/10 C. 1/13 D. 1/10 is my answers

9. anonymous

$\frac{ C_{1}^{48} }{ C _{1}^{52} }=\frac{ 48 }{ 52 }=?$

10. anonymous

im not sure

11. anonymous

@Nnesha @dan815

12. anonymous

@Mehek14

13. anonymous

it would be 1/13 right

14. anonymous

$\frac{ 48 }{ 52 }=\frac{ 12 }{ 13 }$