Sn=A1(1-r^n)/(1-r)
Sum of a finite geometric series formula
We know the sum, number of terms and rate, so you plug those in.
-255=A1(1-(-4)^4))/(1-(-4)
-255=A1(1-256)/5
-255=A1(-255)/5
-1275=A1(-255)
5=A1
Hope this helped! Let me know if you have any questions.
Answer:
Step-by-step explanation:
$0.30
Step-by-step explanation:
1 bar of candy = $0.20
3 bars of candy = $0.50
To solve, multiply for both:
If you pay for each candy bar individually, they each cost $0.20. Multiply 9 with 0.20:
9 x 0.20 = $1.80
If you pay for the candy bars by 3's, they cost $0.50 each pack. Divide 9 with 3, then multiply by 0.50:
9/3 = 3
3 x 0.50 = $1.50
Subtract the total cost of the individual from the pack:
$1.80 - $1.50 = $0.30
. $0.30 is your answer.
Suppose x quarts of the 50% solution
0.5x+0.2*20=0.4(x+20)
0.5x+4=0.4x+8
0.1x=4
x=40
343 = 7 x 7 x 7
the answer is 7,7, and well 7