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
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</span>
Answer:
a) 
b) 
c) 
Step-by-step explanation:
For total cost function
, average cost is given by
i.e., total cost divided by number of units produced.
Marginal average cost function refers to derivative of the average cost function i.e., 
Given:
Average cost = 
a)
At x = 50 units,

b)
Average cost = 
c)
Marginal average cost:
Differentiate average cost with respect to 
Take 
using quotient rule, 
Therefore,

Answer:
The difference of 8 times a number r and 12 is solved for a number r and is given by 
Step-by-step explanation:
Given problem is the difference of 8 times a number r and 12
It can be written as

To simplify the above expression :
8r-12

( using addition property of equality )

(using division property of equality )

Therefore 
Therefore the difference of 8 times a number r and 12 is solved for a number r and is given by 
U do 4/20 = p/100 then u cross multiply the 4 with 100 getting u 400, then divide the 400 by 20, giving u the answer of 20%
Answer:
C
Step-by-step explanation:
Substitute n = 8 into the explicit rule
= -
× 
= -
× 
= -
= - 625 → C