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
A good way to find the answer to these questions is to find it algebraically. Let's call the first number 'n'.
n + (n + 2) + (n + 4) = 54
3n + 6 = 54
3n = 48
n = 16
Therefore the numbers are 16, 18, 20
Answer:
2.5 miles per hour
Step-by-step explanation:
ok, so we already know how long she walked in 1/2 hour and we need to find out how many miles in one full hour. So, i multiplied 1 1/4 times two to make up the one full hour and I got 2.5 miles. So the rate is 2.5 mph.
Answer:
Step-by-step explanation:
The scale factor is given as 1:500,000
i.e. original 500,000 is represented as 1 inch in the map
Hence if 12.7 inches on the map, this is a question of direct variation
So actual distance = 12.7(500000) = 6350000
The speed of one car is 'S'. The speed of the other car is (S + 10).
In 5 hours, the first car travels (5S) miles, and the other car travels 5(S + 10) miles.
Since they're going in opposite directions, the distance between them at any time
is the sum of the distance that each one has traveled.
500 = (5S) + 5(S + 10)
500 = 5S + 5S + 50
500 = 10S + 50
Subtract 50 from each side:
450 = 10S
Divide each side by 10
S = <u>45</u>
S + 10 = <u>55</u>
