Answer:
d = 24
Step-by-step explanation:
The area of a circle is given by A = π * r²
We are told the area of the clock is 144π.
Let's clear the formula for the radius:
r² = A / π
r² = 144π / π
r² = 144
r = √144
r = 12
The diameter is two times the radius, d = 2r = 2*12 = 24.
175 mL at 25% concentration of alcohol contains 0.25 (175 mL) = 43.75 mL of alcohol. If <em>v</em> is the amount of the 70% solution that you use, then that amount contains 0.7<em>v</em> mL of alcohol.
Mixing these two yields a total volume of 175 mL + <em>v</em>, and it contains 43.75 mL + 0.7<em>v</em> alcohol. You want to end up with a concentration of 45%, which means the ratio of the amount of alcohol to the total volume needs to be 0.45:
(43.75 mL + 0.7<em>v</em>) / (175 mL + <em>v</em>) = 0.45
Solve for <em>v</em> :
43.75 mL + 0.7<em>v</em> = 0.45 (175 mL + <em>v</em>)
43.75 mL + 0.7<em>v</em> = 78.75 mL + 0.45<em>v</em>
0.25<em>v</em> = 35 mL
<em>v</em> = 140 mL
The correct answer for the question that is being presented above is this one:
We want to pull 11 (this means not including 12) or less from the bag and there are 100 possibilities
= 11/100
So the probability is <span>11/100</span>
8 hours. 125 - 5 = 120. 120 / 15 = 8. Kelly will need to tutor for 8 hours minimum to buy the dress.
