A service station checks Mr. Smith's radiator and finds it contains only 40% antifreeze. If the radiator holds 20 quarts and is full, how many quarts must be replaced with pure antifreeze in order to bring it up to a required 80% antifreeze?

8 quarts

Step-by-step explanation:

Step One: Figure out how much 40% is by making an equation:

Since we are looking for a percentage, we use cross multiplication to find X.

Step Two: multiply 20 by 40 to start cross multiplying:

20 times 40 is 800, so replace the 40 by 800 in the equation.

Step Three: divide 800 by 100, and we will have X:

800/100=8

X=8 aka 8 quarts

I hope this helps!

pls give thx and brainliest :D

3,750 deer

step-by-step explanation:

1,500 is 15 times larger than 100

lets make 250 15 times larger.

3750 deer

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m