Answer:
1/20
Step-by-step explanation:
The only way it can equal 2 is if both spinners land on 1 because 1 + 1 = 2.
The probability of the 1st spinner landing on 1 is 1/4.
The Probability of the 2nd spinner landing on 1 is 1/5.
To find out the Probability of them landing together it would be 1/5 times 1/4 which equals 1/20.
Lets make k equal to Kate's age and j equal to Joey's age. If in 5 years Kate will be twice as old as Joe, you can write the equation k+5=2(j+5) and then simplify it to make it easier to work with.
k+5=2(j+5)
k+5=2j+10
k+5-2j=10
k-2j=5
since we know that right know Kate is 11 years older than Joey, you can write the equation k+j=11. Since you know have two equations with with the same variable, you can make a system of equations as fallows:
k-2j=5
k+j=11
Since you need to figure out how old Joey is, you need to somehow get k to cancel out. The easiest thing to do for this problem is to is multiply the top equation by -1 to get:
-k+2j=-5 (you have to add the bottom equation to the top equation)
k+j=11 (-k+k=0, 2j+j=3j, and -5+11=6)
Since k got canceled out, you are left with the equation 3j=6 which means j=2.
Therefore, Joey's current age is 2.
I hope this helps.
We must find UNIQUE combinations because choosing a,b,c,d... is the same as d,c,b,a...etc. For this type of problem you use the "n choose k" formula...
n!/(k!(n-k)!), n=total number of choices available, k=number of choices made..
In this case:
20!/(10!(20-10)!)
20!/(10!*10!)
184756
5.2g weighs more because A handful of paper clips is 5.2 grams. A handful of push pins is 500 centigram a. Which handful weighs more? So 1c equals .o1 grams so isn't it 5.2 g compared to .05 grams which then means the paper clips are heavier?
