Answer:
0.01863, yes preference
Step-by-step explanation:
given that a class consists of 12 boys and 12 girls. The teacher picks five students to present their work to the rest of the class and says that the five students are being selected at random
Here selecting any 5 students from the group of total 24 students is combination because order does not matter.
Total no of ways of selecting any 5 from total 24 = 
No of ways of selecting only 5 girls = No of ways of selecting random 5 girls from total 12 girls
= 
a) the probability be that all five students
selected are girls=
b) Since the probability for selecting all girls is very small and near to 0, it is unusual to select all girls if done at random. Hence the teacher had a preference for girls.
When vinegar, an acid, is mixed with baking soda, a base, the reaction is similar to the reaction of Alka-Seltzer and water; a salt, water and carbon dioxide are produced.
Answer:
I'm pretty sure it's 31
Step-by-step explanation:
perimeter you add all the sides
It depends on what you are trying to calculate but the most common way I go to find percentage is to multiply by the number in decimal for ie. 50% = .5.
If you are looking for a way to do it quickly in your head I always take find out what 10% is like in the case of 100 it would be 10 so if I want to find 15% I know I can find 10% and if I cut what 10% is in half I will find 5% so likewise if I add what 10%+5% I will end up with 15%. For example, 10% of 100 is 10 half of 10 is 5 and 10+5 equals 15. If you need to find something like 20% or 30% I know that I can find 10% and instead of dividing(cutting it in half) I can multiply by 2 or 3. 10% + 10% =20%
I hope it helps, if you have more questions let me know!
