Answer:
10
Step-by-step explanation:
Let c = sum of ages of all children.
mean age of all children = c/15 = 7
c = 15 * 7 = 105
The sum of the ages of all children is 105.
Let b = sum of ages of the 9 boys.
mean age of boys = b/9 = 5
b = 9 * 5 = 45
The sum of the ages of the boys is 45.
The sum of the ages of the girls is c - b.
c - b = 105 - 45 = 60
The number of girls is 15 - 9 = 6
mean age of girls = (sum of ages of the girls)/(number of girls) =
= 60/6 = 10
The answer is 68 because is repeating 3 times
3x27=81 so 81 is a multiple of 3
there is no integer x for which 4x=46 so 46 is not a multiple of 4
there is no integer x for which 7x=55 so 55 is not a multiple of 7
72 = 8*9 so 72 is a multiple of 9
there is no integer x for which 6x=45 hence 45 is not a multiple of 6
9514 1404 393
Answer:
C. 3√2 units
Step-by-step explanation:
The diagonal of a square is √2 times the side length. For a square with side length 3, the diagonal is 3√2.
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If you like, you can see this using the Pythagorean theorem.
d² = s² + s² . . . . . where d is the diagonal, and s is the side
d² = 2s²
d = √(2s²) = s√2
For s=3, ...
d = 3√2
Sorry I am a little late...
a = -2
b = -9
Here is how to solve the problem.
First thing I did was multiply the first equation by -2 so that we can eliminate the the b. After you multiply it by -2, your new equation is -16a + 8b = -40.
You leave the second equation alone and all you do is combine like terms. So -16a+5a is -11. And you eliminate the b. Then you're going to do -40+62 which is 22. So it's -11a=22 and then you have to solve for a. What I did was I multiplied the whole thing by minus to turn the a positive. So then it's 11a=-22. Pretty easy, the final step is to simplify. -22/11 is -2. ;D
So there you have your first answer.
a = -2
Now we're going to use the first answer to help us find b.
For the second equation, all you're going to do is plug in that a.
5 (-2)-8b=62
-10 - 8b = 62
Now we move the -10 to the other side...
-8b = 62 + 10
-8b = 72
Multiply the whole thing by negative once again to turn the b positive.
Now we have 8b = -72
The final step is to simplify. -72/11 = -9
b = -9
Hope this makes sense! Also I had the same question on my test and I got it right. :)