Please help so lost, it is not making any sense

Ellen drove 357.9 miles. Her car gets about 21 miles per gallon. Which is the best estimate of how many gallons of gas Ellen use

olga55 [171]

The best thing to do is to divide the amount she has driven (357.9) by the miles (21)
As you're looking for an estimate, you have to round them.
357.9 rounds to 360
21 rounds to 20
Therefore, you've got to divide them
360/20= 18
Therefore, Ellen has driven approximately 18 miles
Hope this helps :)

7 0

3 years ago

Read 2 more answers

A family eats at a restaurant. The bill was $54. The family leaves a tip and spends $60 total. How much was the tip as a perenta

gizmo_the_mogwai [7]

Answer:

11%

Step-by-step explanation:

60 - 54 = $6 The tip is $6 since they were meant to pay $54 but gave $6 extra.

The bill is $54.

6/54 = 0.1 recurring

0.1 × 100 = 11.1%

11% is the percentage.

I hope that helps!! ^-^

8 0

2 years ago

Write an equation of the perpendicular bisector of the segment with the endpoints (8,10) and ( -4,2).

ale4655 [162]

Answer:

The required equation is:

$y = -\frac{3}{2}x+9$

Step-by-step explanation:

To find the equation of a line, the slope and y-intercept is required.

The slope can be found by finding the slope of given line segment. A the perpendicular bisector of a line is perpendicular to the given line, the product of their slopes will be -1 and it will pass through the mid-point of given line segment.

Given points are:

$(x_1,y_1) = (8,10)\\(x_2,y_2) = (-4,2)$

We will find the slope of given line segment first

$m = \frac{y_2-y_1}{x_2-x_1}\\= \frac{2-10}{-4-8}\\=\frac{-8}{-12}\\=\frac{2}{3}$

Let m_1 be the slope of perpendicular bisector then,

$m.m_1 = -1\\\frac{2}{3}.m_1 = -1\\m_1 = \frac{-3}{2}$

Now the mid-point

$(x,y) = (\frac{x_1+x_2}{2} , \frac{y_1+y_2}{2})\\= (\frac{8-4}{2} , \frac{10+2}{2})\\=(\frac{4}{2}, \frac{12}{2})\\=(2,6)$

We have to find equation of a line with slope -3/2 passing through (2,6)

The equation of line in slope-intercept form is given by:

$y = m_1x+b$

Putting the value of slope

$y= -\frac{3}{2}x+b$

Putting the point (2,6) to find the y-intercept

$6 = -\frac{3}{2}(2)+b\\6 = -3+b\\b = 6+3 =9$

The equation is:

$y = -\frac{3}{2}x+9$

7 0

2 years ago

An English teacher needs to pick 9 books to put on his reading list for the next school year, and he needs to plan the order in

Nikitich [7]

Answer: $4.37\times10^3$

Step-by-step explanation:

Given : Number of choices for novels = 4

Number of choices for plays = 6

Number of choices for poetry books = 5

Number of choices for nonfiction books = 5

Total books =4+6+5+5=20

If he wants to include all 4 novels, then the number of books left to select = 9-4=5

Remaining choices for books = 20-4=16

Number of combinations of n things taking r at a time : $\dfrac{n!}{r!(n-r)!}$

Then, the number of different reading schedules are possible :_

$^4C_4\times^{16}C_5\\\\=\dfrac{4!}{4!(4-4)!}\times\dfrac{16!}{5!(16-5)!}\\\\=(1)\times\dfrac{16\times15\times14\times13\times12\times11!}{120\times11!}\\\\=4368=4.368\times10^3\approx4.37\times10^3$

Hence, the required answer is $4.37\times10^3$ .

8 0

3 years ago

Maria practice the piano 5/6 of an hour everyday. How many hours does she practice in 4 days

S_A_V [24]

Answer:
10/3 hours

Explanation:
If Maria practices 5/6 hours a day, then she practices (5/6)(4) hours in 4 days.

(5/6)(4)=20/6

20/6 can be simplified to 10/3 hours.

I hope this helps!

3 0

2 years ago