The sum of the first n terms in a geometric sequence given the first term (a1) and the common ratio (r) is calculated through the equation,
<span>Sn </span>= (<span><span><span>a1</span>(1−<span>r^n</span>) / (</span><span>1−r)
Substituting the known terms,
Sn = (20)(1 - (1/4)^4)) / (1 - 1/4)
Sn = 26.5625
Thus, the sum of the first four terms is 26.5625. </span></span>
Better deal normlly means the rate that cost less
rate=cost/amount
9=cost and 3/4 bushel = amount for one store
3/4=0.75
9/0.75=12/1 aka $12/1bushel
9 =cost and 2/3 bushel =amount for another
2/3=about 0.66666
9/0.66666=13.5/1 aka $13.5/1 bushell
compare
12 dollars per bushe vs 13.5 dollar per bushel
12 is cheaper
therefor $9 For 3/4 bushel is better deal
It seems that some the work is already here, but I'd be glad to!! So for #3 which is 9x^2+15x, we can factor out both a 3 and an x (3x) so we know that 3x * 3x =9x^2 and 3x * 5 = 15x so once we take the 3x out of the equation, we are left with 3x(3x+5) and that's as far as you can factor.
For #4, we see that the common factor is 10m because 10m * 2n = 20mn and 10m * 3 = 30m so once we take 10m out of the original, it becomes 10m(2n-3)
For #5, this one the common factor is 4xy because 4xy * 2xy=8x^2y^2 and 4xy*x= 4x^2y and 4xy*3=12xy so once we take the 4xy out of the equation, it becomes 4xy(2xy-x-3)
Hope this helps!
Answer:
5n
Step-by-step explanation:
cost of one helmet = $5
let 'n' be the number of person that is n=1,2,3,4........
note that the value of n is always a natural number
therefore the expression = 5n
where 5 is the cost one helmet
n is the number of persons
Answer:
Cos 74°= Sin 16°
Sin 20°= Cos 70°
Sin A°=Cos (90°- A°)
Step-by-step explanation:
This is because the three pairs are complementary i.e they add up to 90° and in trigonometric ratios, complementary ratios are equal.