10^-10 in decimal form is 0.000000001. Because the exponent is negative, you move the decimal point ( decimal point is at the end of 0 of the base number 10) 10 place to the right of 10 and u get the answer above. I discarded the 0 later in the answer because now that you've moved the decimal, that 0 have no value. But when forming it in decimal you have to use that 0 or you will get a wrong answer, instead of eight 0's, you will end up with nine 0's.
Answer: 3.499 now 3.079 is correct
Let the number of hours be x.
70 + 80x < 100x
20x > 70
x > 3.5
Answer:
its A.
Step-by-step explanation:
I actually dont know I didnt solve it. i guessed and got it right lol
We have 10 ml of 20% acid to which we need to add "x" milliliters of 100% acid to make 50% acid.
.20 * 10 + 1.00x = .50 * (10 +x)
in which "x" is the volume of the 100% acid to be added.
2 + x = 5 + .5 x
.5x = 3
x = 6 milliliters
Source:
http://www.1728.org/mixture.htm
Scroll down to problem B
