All categories

3 years ago

Help me plz only 3 questions and answer all 3 of them

Mathematics

1 answer:

a_sh-v [17]3 years ago

7 0

Ok so this is the first page
1.
78 pizzas. 20% of 65 is 13. Add that to 65 and you get 78 pizzas.
It is a 1.08% decrease. When you divide 65/60 you get 1.08. Im not 100% sure about this one

2.
Online store=$208 and the superstore=$224
The difference is $16 so it would be cheaper to get it at the online store

3.
It is $4000. For the first year you would multiply $20,000 by 5% which is 20000*.05=1000. Then multiply 1000 by 4 years to get $4,000
Instead of multiplying the 1000 by 4, multiply by 2 to get 2000. Subtract 4000-2000 to get 2000. You saved $2,000

You might be interested in

Operations with Radical Expressions

lisov135 [29]

Answer: $30\sqrt{11}$

Step-by-step explanation:

$3\sqrt{50} * \sqrt{22}$

= $3\sqrt{5*5*2} * \sqrt{2*11}$

= $3\sqrt{5*5*2*2*11}$

= $3*5*2\sqrt{11}$

= $30\sqrt{11}$

******************************************

Answer: $6\sqrt{30}$

Step-by-step explanation:

$\sqrt{20} * \sqrt{3} * \sqrt{18}$

= $\sqrt{2*2*5} * \sqrt{3} * \sqrt{3*3*2}$

= $\sqrt{2*2*5*3*3*3*2}$

= $2*3\sqrt{5*3*2}$

= $6\sqrt{30}$

********************************************

Answer: $-\sqrt{5}$

Step-by-step explanation:

$4\sqrt{20} - 3\sqrt{45}$

= $4\sqrt{2*2*5} - 3\sqrt{3*3*5}$

= $4*2\sqrt{5} - 3*3\sqrt{5}$

= $8\sqrt{5} - 9\sqrt{5}$

= $-\sqrt{5}$

********************************************

Answer: $4\sqrt{5}$

Step-by-step explanation:

$2\sqrt{5} + 3\sqrt{5} - \sqrt{5}$

= $(2+3-1)\sqrt{5}$

= $4\sqrt{5}$

********************************************

Answer: $46\sqrt{2}$

Step-by-step explanation:

$4\sqrt{32} + 6\sqrt{50}$

= $4\sqrt{2*2*2*2*2} + 6\sqrt{2*5*5}$

= $4*2*2\sqrt{2} + 6*5\sqrt{2}$

= $16\sqrt{2} + 30\sqrt{2}$

= $46\sqrt{2}$

7 0

3 years ago

Solve the triangle.

saw5 [17]

Answer:

Step-by-step explanation:

because c is shorter than a we know C is a smaller angle than A

so the first choice is out.

use the law of cosines to find b

$b^{2}$ = $a^{2} +c^{2} -2*a*c*cos(B)$

$b^{2}$ =1681+400-1326.787871

$b^{2}$ = 754.21219

b= $\sqrt{754.21219}$

b= 27.46292

so the last choice looks good

5 0

2 years ago

HELPPPPPPP PLSSSSSSSSSS

vichka [17]

Answer:

Step-by-step explanation:

I checked it and it’s right hope this helps!!

6 0

2 years ago

The tables represent two linear functions in a system,

Alenkasestr [34]

Answer:

Step-by-step explanation:

The slope-intercept form of an equation of a line:

$y=mx+b$

m - slope

b - y-intercept

The formula of a slope:

$m=\dfrac{y_2-y_1}{x_2-x_1}$

First table:

(-4, 26), (0, 10) → b = 10

$m=\dfrac{10-26}{0-(-4)}=\dfrac{-16}{4}=-4$

$\boxed{y=-4x+10}$

Second table:

(-4, 14), (0, 2) → b = 2

$m=\dfrac{2-14}{0-(-4)}=\dfrac{-12}{4}=-3$

$\boxed{y=-3x+2}$

We have the system of equations:

$\left\{\begin{array}{ccc}y=-4x+10&(1)\\y=-3x+2&(2)\end{array}\right\\\\\text{Put (1) to (2):}\\\\-4x+10=-3x+2\qquad\text{subtract 10 from both sides}\\-4x=-3x-8\qquad\text{add 3x to both sides}\\-x=-8\qquad\text{change the signs}\\x=8\\\\\text{Put the value of x to (2):}\\\\y=-3(8)+2\\y=-24+2\\y=-22$

5 0

2 years ago

Suppose X, Y, and Z are random variables with the joint density function f(x, y, z) = Ce−(0.5x + 0.2y + 0.1z) if x ≥ 0, y ≥ 0, z

kompoz [17]

$f_{X,Y,Z}(x,y,z)=\begin{cases}Ce^{-(0.5x+0.2y+0.1z)}&\text{for }x\ge0,y\ge0,z\ge0\\0&\text{otherwise}\end{cases}$

is a proper joint density function if, over its support, $f$ is non-negative and the integral of $f$ is 1. The first condition is easily met as long as $C\ge0$ . To meet the second condition, we require

$\displaystyle\int_0^\infty\int_0^\infty\int_0^\infty f_{X,Y,Z}(x,y,z)\,\mathrm dx\,\mathrm dy\,\mathrm dz=100C=1\implies \boxed{C=0.01}$

b. Find the marginal joint density of $X$ and $Y$ by integrating the joint density with respect to $z$ :

$f_{X,Y}(x,y)=\displaystyle\int_0^\infty f_{X,Y,Z}(x,y,z)\,\mathrm dz=0.01e^{-(0.5x+0.2y)}\int_0^\infty e^{-0.1z}\,\mathrm dz$

$\implies f_{X,Y}(x,y)=\begin{cases}0.1e^{-(0.5x+0.2y)}&\text{for }x\ge0,y\ge0\\0&\text{otherwise}\end{cases}$

Then

$\displaystyle P(X\le1.375,Y\le1.5)=\int_0^{1.5}\int_0^{1.375}f_{X,Y}(x,y)\,\mathrm dx\,\mathrm dy$

$\approx\boxed{0.12886}$

c. This probability can be found by simply integrating the joint density:

$\displaystyle P(X\le1.375,Y\le1.5,Z\le1)=\int_0^1\int_0^{1.5}\int_0^{1.375}f_{X,Y,Z}(x,y,z)\,\mathrm dx\,\mathrm dy\,\mathrm dz$

$\approx\boxed{0.012262}$

7 0

2 years ago