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

Can someone help me with this please??

lana66690 [7]

So start with the top one and end w the bottom

6 0

2 years ago

URGENT, PLEASE HELP! (3/5) -50 POINTS- !please no wrong answers for the points.! A) <img src="https://tex.z-dn.net/?f=y%20%3D%20

shtirl [24]

Answer:

B y = -1/2x + 7/2

Step-by-step explanation:

We know that it has a negative slope since the points go from the top left to the bottom right

We can eliminate A and D

The y intercept is where it crosses the y axis

It should cross somewhere between 2 and 4

C has a y intercept of 9 which is too big

Lets verify with a point

x = -4

y = -4(-4)+9 = 16+9 = 25 (-4,25) not even close to being near the points on the graph

checking B

y = -1/2 (-4) +7/2

= 2 + 7/2 = 11/2 = 5.5 it seems reasonable

5 0

3 years ago

Read 2 more answers

Consider the line y = 9x-5.

goldenfox [79]

Answer:

$4 \times {4}^{ - 5 \times 4}$

7 0

2 years ago