A geometric sequence is a sequence in which there is a common ratio between any two consecutive terms. In this case if X:Y:Z are in the ratio of 2:7:8 the multiplying by a constant k, we have X=2k, Y= 7k and Z=8k.
Then if X, Y-12, Z form a Geometric sequence, it means X/Y-12=Y-12/Z which is the same as 2k/7k-12=7k-12/8k if we cross multply, we get
16k²= 49k²-168k +144
33k²-168k+144 =0 solving for k
k = 4 or 1.091 if we take the whole number to find the values of X,Y and z,
X= 8, Y= 28 and Z=32
11: B
12: C
They are both supplementary angles meaning they add to 180 degrees
Let h = the number of horses in the field
Let c = number of cows in the field
There are 2 more horses than cows in the field. Therefore
h = c + 2
or
c = h - 2 (1)
There are 15 animals in the field. Therefore
h + c = 15 (2)
Substitute (1) into (2).
h + (h - 2) = 15
2h - 2 = 15
Answer:
The correct equation is
2h - 2 = 15
A) the probability it is brown would be 50%; the probability it is yellow or blue would be 35%; the probability it is not green is 95%; the probability it is striped is 0%.
B) the probability of all brown would be 12.5%; the probability that the third one is the first red one drawn is 8.1%; the probability that none are yellow is 61.4%; the probability that at least one is green is 14.3%.
Explanation:
A) The probability that it is brown is the percentage of brown we have. Brown is not listed, so we subtract what we are given from 100%:
100-(15+10+20+5) = 100-(50) = 50%. The probability that one drawn is yellow or blue would be the two percentages added together: 15+20 = 35%. The probability that it is not green would be the percentage of green subtracted from 100: 100-5=95%. Since there are no striped candies listed, the probability is 0%.
B) Since we have an infinite supply of candy, we will treat these as independent events. All 3 being brown is found by taking the probability that one is brown and multiplying it 3 times:
0.5*0.5*0.5 = 0.125 = 12.5%.
To find the probability that the first one that is red is the third one drawn, we take the probability that it is NOT red, 100-10 = 90% = 0.9, for the first two, and the probability that it IS red, 10% = 0.1, for the last:
0.9*0.9*0.1 = 0.081 = 8.1%.
The probability that none are yellow is found by raising the probability that the first one is not yellow, 100-15=85%=0.85, to the third power:
0.85^3 = 0.614 = 61.4%.
The probability that at least one is green is computed by subtracting 1-(probability of no green). We first find the probability that all three are NOT green:
0.95^3 = 0.857375
1-0.857375 = 0.143 = 14.3%.
