40% of 15 L = 6 L of acid
20% of 25 L = 5 L of acid
This means the mixture contains a total of 11 L of acid, and with a total volume of 15 L + 25 L = 40 L, that means the mixture is at a concentration of
(11 L acid) / (40 L solution) = 0.275 = 27.5%
Answer:
answer is 12. they may want it in format of 12.00
number of accurate weather forecast over total number of days
21/36 to percentage is 58.33%
hence, 58.33% is the probability that the forecast tomorrow will be accurate.