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3 years ago

The question on the bottom

Mathematics

1 answer:

TEA [102]3 years ago

5 0

Answer:

9th grade student=33.3%, unit 7=45%

Step-by-step explanation:

You might be interested in

Pleasantburg has a population growth model of P(t)=at2+bt+P0 where P0 is the initial population. Suppose that the future populat

yulyashka [42]

Answer:

The population will reach 34,200 in February of 2146.

Step-by-step explanation:

Population in t years after 2012 is given by:

$P(t) = 0.8t^{2} + 6t + 19000$

In what month and year will the population reach 34,200?

We have to find t for which P(t) = 34200. So

$P(t) = 0.8t^{2} + 6t + 19000$

$0.8t^{2} + 6t + 19000 = 34200$

$0.8t^{2} + 6t - 15200 = 0$

Solving a quadratic equation:

Given a second order polynomial expressed by the following equation:

$ax^{2} + bx + c, a\neq0$ .

This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})$ , given by the following formulas:

$x_{1} = \frac{-b + \sqrt{\bigtriangleup}}{2*a}$

$x_{2} = \frac{-b - \sqrt{\bigtriangleup}}{2*a}$

$\bigtriangleup = b^{2} - 4ac$

In this question:

$0.8t^{2} + 6t - 15200 = 0$

So $a = 0.8, b = 6, c = -15200$

Then

$\bigtriangleup = 6^{2} - 4*0.8*(-15100) = 48356$

$t_{1} = \frac{-6 + \sqrt{48356}}{2*0.8} = 134.14$

$t_{2} = \frac{-6 - \sqrt{48356}}{2*0.8} = -141.64$

We only take the positive value.

134 years after 2012.

.14 of an year is 0.14*365 = 51.1. The 51st day of a year happens in February.

So the population will reach 34,200 in February of 2146.

6 0

2 years ago

True or false?<br> All quadrilaterals are also rhombuses.

Molodets [167]

Answer:

It's false

All quadrilaterals are also rhombus, <u>False</u>

4 0

2 years ago

Read 2 more answers

Based on the graph what are the approximate solutions to the equation -2x+4=(0.25)x?

konstantin123 [22]

4=2.25x add 2x on both sides
1.78=x subtract 2.25 on both sides

5 0

2 years ago

The height distribution of NBA players follows a normal distribution with a mean of 79 inches and standard deviation of 3.5 inch

Shtirlitz [24]

Answer:

The probability will be "0.0111".

Step-by-step explanation:

The given values are:

Mean,

$\mu$ = 79

Standard deviation,

$\sigma$ = 3.5

Now,

⇒ $\sigma\bar x = \frac{\sigma}{\sqrt n}$

$= \frac{3.5}{\sqrt 16}$

$=0.875$

⇒ $P(\bar x > 81) = 1 - P(\bar x < 81)$

So,

= $1 - P{\frac{(\bar x - \mu \bar x )}{ \sigma \bar x} < \frac{(81 - 79) }{0.875} ]$

= $1 - P(z < 2.2857)$

= $0.0111$

7 0

2 years ago

The Law and Order detectives enter a house at 11:30 am and found a man on the floor murdered. They take his body temperature fin

taurus [48]

Answer:

Time of murder = 10:39 am

Step-by-step explanation:

Let the equation of exponential function representing the final temperature of the body after time 't' is,

f(t) = $a(e)^{nt}$

Here, a = Initial temperature

n = Constant for the change in temperature

t = Duration

At 11:30 am temperature of the body was 91.8°F.

91.8 = $98.6(e)^{nt}$ --------(1)

Time to reach the body to the morgue = 12:30 pm

Duration to reach = 12:30 p.m. - 11:30 a.m.

= 1 hour

Therefore, equation will be,

84.4 = $91.8(e)^{n\times 1}$

eⁿ = $\frac{84.4}{91.8}$

ln(eⁿ) = ln(0.9194)

n = -0.08403

From equation (1),

91.8 = $98.6(e)^{-0.08403t}$

$(e)^{0.08403t}=\frac{98.6}{91.8}$

$ln[(e)^{0.08403t}]=ln[\frac{98.6}{91.8}]$

0.08403t = 0.07146

t = 0.85 hours

t ≈ 51 minutes

Therefore, murder was done 51 minutes before the detectives arrival.

Time of murder = 11:30 - 00:51

= 10:90 - 00:51

= 10:39 am

7 0

2 years ago