Answer:
452.16
Step-by-step explanation:
πr^2 ... then substitute the numbers accordingly!
Answer: the number of shoppers on the first day is 125
Step-by-step explanation:
The number of shoppers is 20% more than the numbers of shoppers the day before. It means that the number of shoppers is increasing in geometric progression. The formula for determining the sum of n terms, Sn of a geometric sequence is expressed as
Sn = (ar^n - 1)/(r - 1)
Where
n represents the number of term in the sequence.
a represents the first term in the sequence.
r represents the common ratio.
From the information given,
r = 1 + 20/100 = 1.2
n = 4(first 4 days)
S4 = 671
Therefore, the expression for the first 4 days is
671 = (a × 1.2^(4) - 1)/1.2 - 1
671 = (a × 1.2^(4) - 1)/0.2
671 = 1.0736a/0.2
671 = 5.368a
a = 671/5.368
a = 125
Answer:
200
Step-by-step explanation:
C = 0.007x² − 2.8x + 100
There are two ways we can find the minimum. The first is by noticing that this is an upwards parabola, so the minimum is at the vertex. For y = ax² + bx + c, the vertex is at x = -b/(2a).
x = -(-2.8) / (2 × 0.007)
x = 200
Alternatively, we can minimize C using calculus. Take the derivative with respect to x and set to 0:
dC/dt = 0.014x − 2.8
0 = 0.014x − 2.8
x = 200
Answer:
x = -1/7
Step-by-step explanation:
simplify by bringing all the x to the left and all the constants to the right:
6x + x = 1 - 2
7x = -1 (divide by 7)
x = -1/7
