Answer How many liters of a 20% acid solution should be mixed with 30 liters of 50% acid solution in order to obtain a 40% solution. ... x=15 liters 15*(.20 pure acid)=3 liters 30*(.50 pure acid)=15 liters That is 18 liters pure acid That is 45 liters solution *0.45 pure acid=18 liters.
Step-by-step explanation:
Answer:
Not necessarily, because this wasn't an experiment.
Step-by-step explanation:

Explanation:
Since we have given that
The prices of three t-shirts styles i.e $24, $30, $36 with their probability is given by

As we know that,


Now,

and

So,

So, the expected value of a t-shirt = $31.
Perhaps the easiest way to solve this problem is to convert 13 into a fraction that has the same denominator as 7 5/8.
Convert both to improper fractions:
7 5/8 turns into 61/8, and
13 turns into 104/8.
Then, subtract 61/8 from 104/8:
104/8-61/8=43/8.
Simplify (mixed fraction):
5 3/8.
The second ribbon has a length of 5 3/8 meters.
10 1/2-4 1/4= 6 1/4. 6 1/4-3 2/3= 2 7/12. They used 2 7/12 ft or 2ft 7in of wood to fix the stairs.