Answer:
Area of the shaded region = 1.72r²
Step-by-step explanation:
Radius of the circle = r
Length of the rectangle = 4r
Width of the rectangle = 2r
Area of the circle = πr²
Area of the rectangle = Length × Width
= 4r × 2r
= 8r²
Area of the shaded region = Area of the rectangle - 2 × Area of the circle
= 8r² - 2 × πr²
= 8r² - 2πr²
= r²(8 - 2π)
= r²(8 - 2 × 3.14)
= r²(8 - 6.28)
= 1.72r²
Answer:
$425
Step-by-step explanation:
Let x represent the number of bracelets made and let y represent the number of necklace made.
Since the craftsman has 1000 beads to work with, hence:
10x + 20y ≤ 1000 (1)
Also, the craftsman has 1600 minutes, hence:
10x + 40y ≤ 1600 (2)
From ploting equations 1 and 2 on the geogebra online graphing, we can see that the solution to the problem is (40, 30).
Since the bracelet costs $5 and a necklace costs $7.50, hence the maximum revenue is:
Revenue = 5x + 7.5y = 5(40) + 7.5(30) = $425
Answer:
The number of bacteria at initial = 187
Step-by-step explanation:
Given that the population of bacteria in a culture grows at a rate proportional to the number of bacteria present at time t.
Integrating both side we get
㏑ N = k t + C ------- (1)
Now given that after 3 hours it is observed that 500 bacteria are present and after 10 hours 5000 bacteria are present.
⇒ ㏑ 500 = 3 k + C -------- (2)
⇒ ㏑ 5000 = 10 k + C ------ (3)
⇒ ㏑ 5000 - ㏑ 500 = 7 k
⇒ ㏑ = 7 k
⇒ ㏑ 10 = 7 k
⇒ k = 0.329
Put this value of k in equation (2),
⇒ ㏑ 500 = 3 × 0.329 + C
⇒ C = 5.23
Put this value of C in equation 1 we get,
⇒ ㏑ N = k t + 5.23
Initially when t = 0 , then
⇒ ㏑ N = 5.23
⇒ N = 187
Thus the number of bacteria at initial = 187