Answer:
D
Step-by-step explanation:
Answer:
1. 40%
2. The theoretical probability is 3% greater than the experimental probability.
Step-by-step explanation:
We are informed that a number cube is rolled 20 times and the number 4 is rolled 8 times. The experimental probability of rolling a 4 is;
(the number of times a 4 was rolled)/(total number of rolls)
8/20 = 0.4
0.4*100 = 40%
The experimental probability of obtaining at least one tails, one or more tails, is represented in mathematical notation as;
P(HT or TH or TT)
The above events are mutually exclusive, thus;
P(HT or TH or TT) = P(HT) + P(TH) + P( TT)
= (22+34+16)/(28+22+34+16)
= 0.72 = 72%
On the other hand, the theoretical probability of obtaining at least one tails,
P(HT or TH or TT) = 3/4
= 75%
This is because there is at least one tail in 3 out of 4 possible outcomes.
Therefore, it is true to say that the theoretical probability is 3% greater than the experimental probability.
Step-by-step explanation:
x²-y²=12
(x-y)(x+y)=12
but x-y=4
4(x+y)=12
x+y=12/4
x+y=3
lets make x the subject of the formula
x=3-y
since x-y=4
(3-y)-y=4
3-y-y=4
-2y=1
y=-1/2
then x=3-y
x=3-(-1/2)
x=(6--1)/2
x=7/2
therefore; x²+2xy+y
=(7/2)²+2×7/2×-1/2+(-1/2)
=49/4-7/2-1/2
=(49-14-2)/4
=33/4
=8.25
=8
