Answer:
x: work a woman can do in 1 day
y: work a girl can do in 1 day
Then
2x + 7y =1/4
4x + 4y =1/3
4x + 14y =2/4 (1)
4x + 4y =1/3 (2)
=> Let (1) - (2), 10y =2/4-1/3 <=>10y = 1/6 <=> y = 1/(6x10) = 1/60 (work)
=> From (2),4x = 1/3 - 4x1/60 => 4x = 16/60 => x = 4/60 (work)
=> 1 day, a woman and a girl can do: 1/60+4/60 = 5/60 =1/12 (work)
Then, the day required for a woman and a girl to complete work: 12 days
The cost function is
c = 0.000015x² - 0.03x + 35
where x = number of tires.
To find the value of x that minimizes cost, the derivative of c with respect to x should be zero. Therefore
0.000015*2x - 0.03 = 0
0.00003x = 0.03
x = 1000
Note:
The second derivative of c with respect to x is positive (= 0.00003), so the value for x will yield the minimum value.
The minimum cost is
Cmin = 0.000015*1000² - 0.03*1000 + 35
= 20
Answer:
Number of tires = 1000
Minimum cost = 20
1 pack of 12 will give 4 students their pencils. 20/4 = 5
Hi there:-)
She has=3+3/4=15/4
She ordered=11+1/2=23/2
Now how many she has in all
(15/4)+(23/2)=15 1/4 ...answer
15 1/4 means 15+1/4=15.25
Hope it helps
