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3 years ago

Please help! provide thorough explanation and use elimination method!!

Mathematics

1 answer:

ICE Princess25 [194]3 years ago

8 0

Multiply both sides of the second equation by 100 to get rid of the decimals:

0.05n + 0.10d = 1.50

==> 5n + 10d = 150

Multiply both sides of the first equation by -5:

n + d = 21

==> -5n - 5d = -105

Add the two equations together:

(5n + 10d) + (-5n - 5d) = 150 + (-105)

Notice that the terms containing n get eliminated and we can solve for d :

(5n - 5n) + (10d - 5d) = 150 - 105

5d = 45

d = 45/5 = 9

Plug this into either original equation to solve for n. Doing this with the first equation is easiest:

n + 9 = 21

n = 21 - 9 = 12

So Donna used 12 nickels and 9 dimes.

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Hey! i’ll give brainliest please help

Elan Coil [88]

Answer:

I would assume it to be the second option, or B.

'The bogs the moose lived in became so soggy that only moose with the largest feet could successfully walk on the bog'

Step-by-step explanation:

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3 years ago

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Chase has 3 gallons of a solution that is 30% antifeeze that he wants to use to winterize his car. How much pure antifreeze shou

makvit [3.9K]

Let x gallons be the amount of pure antifreeze that should be added to the 30% solution to produce a solution that is 65% antifreeze. Then the total amount of antifreeze solution will be x+3 gallons.

There are 30% of pure antifreeze in 3 gallons of solution, then

3 gallons - 100%,

a gallons - 30%,

where a gallons is the amount of pure antifreeze in given solution.

Mathematically,

$\dfrac{3}{a}=\dfrac{100}{30},\\ \\a=\dfrac{3\cdot 30}{100}=0.9\ gallons.$

Now in new solution there will be x+0.9 gallons of pure antefreeze.

x+3 gallons - 100%,

x+0.9 - 65%

$\dfrac{x+3}{x+0.9}=\dfrac{100}{65},\\ \\65(x+3)=100(x+0.9),\\ \\65x+195=100x+90,\\ \\35x=105,\\ \\x=3\ gallons.$

Answer: he should add 3 gallons of pure antifreeze.

8 0

3 years ago

there arre 221 students on a fiel trip five students ride in a van the rest of the students fill the 6 buses enter an equation t

iren2701 [21]

According to the question statement, the total sum of students is 221, which includes the students that ride on bus and the students that ride in a van.

The students that ride in a van are five, the students that ride on bus are 6 times s which is the product of the number of buses and the number of students that are on each bus.

Write all this information into an equation, this way:

$6s+5=221$

Now, solve the equation for s to find the number of students that are on each bus.

$\begin{gathered} 6s+5=221 \\ 6s=216 \\ s=\frac{216}{6} \\ s=36 \end{gathered}$

There are 36 students on each bus.

3 0

1 year ago

A car rental agency advertised renting a car for $ 23.95 per day and $ 0.32 per mile. If Trevor rents this car for 3 days, how

AVprozaik [17]

Y=mx +b plug that in , so the 23.95 would be the flat fee then you add 0.32
250 =23.95+0.32 subtract from both sides then divide the answer is 10 miles

4 0

3 years ago

Read 2 more answers

7 freshmen, 9 sophomores, 8 juniors, and 8 seniors are eligible to be on a committee.

Setler79 [48]

Answer:

i)32C16

ii)1185408

Explanation:

i)Total number of selected/eligible is 7+9+8+8=32

Total ways of selecting dance committee of 16 is

32C16

ii)Total ways of selecting 3 seniors from 8 is 8C3

and Total ways of selecting 6 juniors from 8 is 8C6

ways of selecting 2 sopho from 9 is 9C2

ways of selecting 5 freshman from 7 is 7C5

now, total way of selection come to be

8C3×8C6×9C2×7C5

=56×28×36×21

=1185408

✌️

6 0

3 years ago