Should be D. 2x65=130-20=110
To help with thinking about this, we can say that the 6 gallons of 50% acid contains 3 gallons of pure acid and 3 gallons of filler. This would make the concentration 3/6, or 50%. Adding a gallon of pure acid would shift the concentration to 4/7, or 57.1%.
When the relationship becomes 70%, four gallons of pure acid have been added.
3+4 7
—— = — = 70%
6+4 10
Answer: 35
Step-by-step explanation: So first we take 50 and multiply it by 70%. In decimal form, 70%=0.70. This should give you 35 players that are right handed if you multiply 50*0.70
Answer:angle 1=90 angle 2=45 angle 3=45
Step-by-step explanation:
Answer:
³/5
Step-by-step explanation:
Total = 5 units
Girls = 3 units
~if ⅔ of the girls wear braces
= 2units of girs wear braces
Boys = 2 units
~if ½ of the boys wear braces
= 1unit of boys wear braces
Hence, 2units + 1unit =3 units of the class wears braces.
Total pupils = 5units
total that wear braces out of the whole class = 3/5