Answer: 
Step-by-step explanation:
To find the least common multiply, you must descompose 12 and 15 into their prime factors, as you can see below:
12=2*2*3=2²*3
15=3*5
Choose the common and non common numbers with their greastest exponents:
3*5*2²=60
Now you must choose the common and non common variables with their greastest exponents:
n³
Therefore, you can conclude that the least common multiply is:

23
Those are not the answer:
1) 20 - can be divided by 2
2) 21 - can be divided by 3
3) 22 - can be divided by 2
4) 24 - can be divided by 2 and 4.
5) 25 - can be divided by 5
6) 26 - can be divided by 2
7) 27 - can be divided by 3
8) 28 - can be divided by 2 and 4
Answer:
Question 13: 90, Question 14: y =
, Question 15: x =
, Question 16: y =
.
Step-by-step explanation:
Answer:
If two expressions are equal to each other, and you add the same value to both sides of the equation, the equation will remain equal. When you solve an equation, you find the value of the variable that makes the equation true. In order to solve the equation, you isolate the variable.
1) Our marbles will be blue, red, and green. You need two fractions that can be multiplied together to make 1/6. There are two sets of numbers that can be multiplied to make 6: 1 and 6, and 2 and 3. If you give the marbles a 1/1 chance of being picked, then there's no way that a 1/6 chance can be present So we need to use a 1/3 and a 1/2 chance. 2 isn't a factor of 6, but 3 is. So we need the 1/3 chance to become apparent first. Therefore, 3 of the marbles will need to be one colour, to make a 1/3 chance of picking them out of the 9. So let's say 3 of the marbles are green. So now you have 8 marbles left, and you need a 1/2 chance of picking another colour. 8/2 = 4, so 4 of the marbles must be another colour, to make a 1/2 chance of picking them. So let's say 4 of the marbles are blue. We know 3 are green and 4 are blue, 3 + 4 is 7, so the last 2 must be red.
The problem could look like this:
A bag contains 4 blue marbles, 2 red marbles, and 3 green marbles. What are the chances she will pick 1 blue and 1 green marble?
You should note that picking the blue first, then the green, will make no difference to the overall probability, it's still 1/6. Don't worry, I checked
2) a - 2% as a probability is 2/100, or 1/50. The chance of two pudding cups, as the two aren't related, both being defective in the same packet are therefore 1/50 * 1/50, or 1/2500.
b - 1,000,000/2500 = 400
400 packages are defective each year