First term: a1 = 151
common difference: d = -14 (we decrease by 14 each time, eg, 151-14 = 137)
nth term of this arithmetic sequence is...
an = a1+d(n-1)
an = 151+(-14)(n-1)
an = 151-14n+14
an = -14n+165
This will be used in the formula below
Sn = n*(a1+an)/2
<span>Sn = n*(151+(-14n+165))/2
</span><span>S26 = 26*(151+(-14*26+165))/2 ... replace every n with 26
</span>S26 = -624
The final answer here is choice C) -624
<span>
</span>
Answer:
C ($19.25)
Step-by-step explanation:
First, find how much 1 carton costs, which is $8.75 divided by 5, which is $1.75. So, to find how much 11 cartons cost, we just multiply by 11 to get [tex]\boxed{\$19.25}[\tex]
23) Store A: y=6.30÷2
y=3.15
Store B: y=3.2
Store C: y=3.25x
y=3.25 so Store A sells the cheapest so (A) is the answer
24) the area uses half of the diameter, not the whole diameter. so the answer is 5.5pi^2 (B)
25) 1/2 × 1/2 = 1/4 × 1/2 = 1/8 (D)
26) was done correctly and (D) is the correct answer
27) 2 (x-3) +1 =19
2 (x-3) = 19 - 1
(x-3) = 18 ÷ 2
x-3 = 9
x= 9+3
x=12 (D)
