Answer:
From left to right
All real numbers
All positive real numbers and zero
All real numbers except 2<_x<_5
All real numbers except 1<_x<_4
Step-by-step explanation:
7x + 14 + 3x + 15 = 14x + 14 + 2
10x + 14 = 14x + 16
14 - 16 = 14x - 10x
-2 = 4x
X = - 2/4
X = - 1/2 OR X = - 0.5
Answer:
d
Step-by-step explanation:
Answer: 15/91 which is choice B
=================================================================
There are two methods to find this answer.
Method 1) We have 6 girls and 8+6 = 14 students. The probability of picking a girl is 6/14 = 3/7. After the first girl is chosen, we have 5 girls left out of 14-1 = 13 students overall. The probability of picking another girl (assuming the first selection was a girl) is 5/13. Multiply these probabilities: (3/7)*(5/13) = (3*5)/(7*13) = 15/91
--------------------
Method 2) We can use the nCr combination formula. Order does not matter.
We have nCr = 6 C 2 = 15 ways to pick 2 girls. See the attached image below for the steps (figure 1)
Out of nCr = 14 C 2 = 91 ways to pick 2 students. See the attached image below for the steps (figure 2)
So that's another way to get the answer 15/91.
METHOD 1
f(3) = 20
f(4) = 30
f(5) = 42
f(6) = 56
rate of change
f(4)-f(3)=10
f(5)-f(4)=12
f(6)-f(5)=14
then the average of change is 10+12+14 /3 = 12
METHOD 2 --- faster
rate of change = f(6)-f(3) / 6-3
= (36+18+2)-(9+9+2) / 3
= 36/3 = 12