The sum of a number divided by 8 and 6 is 3

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vovikov84 [41]

Answer:

the answer is D. 40

Step-by-step explanation:

4 0

3 years ago

1990 population was 254 million in 2014 it was 303 what was the percentage increase in the population

Ann [662]

Answer:

19.29%

Step-by-step explanation:

Given

Population in 1990

= 254000000

Population in 2014

= 303000000

Increase = 303000000 - 254000000

= 49000000

% increase in population =

Increase /initial population x 100%

That’s

49000000/254000000 x 100%

0.1929 x 100%

19.29%

The population increased by 19.29%

7 0

3 years ago

Find the length of the following two-dimensional curve. r (t ) = (1/2 t^2, 1/3(2t+1)^3/2) for 0 < t < 16

andrezito [222]

Answer:

r = 144 units

Step-by-step explanation:

The given curve corresponds to a parametric function in which the Cartesian coordinates are written in terms of a parameter "t". In that sense, any change in x can also change in y owing to this direct relationship with "t". To find the length of the curve is useful the following expression;

$r(t)=\int\limits^a_b ({r`)^2 \, dt =\int\limits^b_a \sqrt{((\frac{dx}{dt} )^2 +\frac{dy}{dt} )^2)} dt$

In agreement with the given data from the exercise, the length of the curve is found in between two points, namely 0 < t < 16. In that case a=0 and b=16. The concept of the integral involves the sum of different areas at between the interval points, although this technique is powerful, it would be more convenient to use the integral notation written above.

Substituting the terms of the equation and the derivative of r´, as follows,

$r(t)= \int\limits^b_a \sqrt{((\frac{d((1/2)t^2)}{dt} )^2 +\frac{d((1/3)(2t+1)^{3/2})}{dt} )^2)} dt$

Doing the operations inside of the brackets the derivatives are:

1 ) $(\frac{d((1/2)t^2)}{dt} )^2= t^2$

2) $\frac{(d(1/3)(2t+1)^{3/2})}{dt} )^2=2t+1$

Entering these values of the integral is

$r(t)= \int\limits^{16}_{0} \sqrt{t^2 +2t+1} dt$

It is possible to factorize the quadratic function and the integral can reduced as,

$r(t)= \int\limits^{16}_{0} (t+1) dt= \frac{t^2}{2} + t$

Thus, evaluate from 0 to 16

$\frac{16^2}{2} + 16$

The value is $r= 144 units$

5 0

4 years ago

if a rectangle has an area of 30 square meters and a perimeter of 34 meters . what is the dimensions of the rectangle?

timama [110]

P=2(L+W) and P=34 so

2(L+W)=34

L+W=17 so we can say

L=17-W

A=LW using L from above

A=(17-W)W

A=17W-W^2 and A=30 so

30=17W-W^2

W^2-17W+30=0

W^2-2W-15W+30=0

W(W-2)-15(W-2)=0

(W-15)(W-2)=0

So the dimensions of the rectangle are 15 meters by 2 meters.

7 0

3 years ago

Cement pillars for a porch or 2 feet wide, 2 feet thick, and 8 feet tall, there are six pillars in all what is the total volume

PolarNik [594]

(8)(2)(2)=32
32(6)=192
Final answer: 192ft^3

3 0

4 years ago