Answer:
-49
Step-by-step explanation:
Reduce the expression, if possible, by cancelling the common factors.
It decreased from week one to week two by -1.875, then it started to increase from 0.625 then to 1.5 by week 4
Answer:
Step-by-step explanation:
Jim is 18
Sally: 3 years older than Jim
18 + 3 = 21
Complete question :
The Harris Poll conducted a survey in which they asked, "How many tattoos do you currently have on your body?" Of the 1205 males surveyed, 181 responded that they had at least one tattoo. Of the 1097 females surveyed, 143 responded that they had at least one tattoo. Construct a 95% confidence interval to judge whether the proportion of males that have at least one tattoo differs significantly from the proportion of females that have at least one tattoo. Interpret the interval.
Answer:
(−0.0085 ; 0.0481)
Step-by-step explanation:
Given that :
n1 = 1205 ; x1 = 181 ; n2 = 1097 ; x2 = 143 ; α = 95%
Zα/2 = 1.96 ( Z table)
Confidence interval : (p1 - p2) ± E
E =Zα/2 * √[(p1q1/n1) + (p2q2/n2)]
p1 = x1 /n1 =181/1205 = 0.1502
q1 = 1 - p1 = 1 -0.1502 = 0.8498
p2 = x2/n2 = 143/1097 = 0.1304
q2 = 1 - p2 = 1 -0.1304 = 0.8696
E = 1.96 * √(0.0001059 + 0.0001033)
E = 0.0283
p1 - p2 = 0.1502 - 0.1304 = 0.0198
Lower boundary = 0.0198 - 0.0283 = −0.0085
Upper boundary = 0.0198 + 0.0283 = 0.0481
(−0.0085 ; 0.0481)
Answer: 9 boys remained in the choir.
Step-by-step explanation:
Let x be the number of of boys and y be the number of girls.
In a school choir, 1/2(half) of the members were girls.
i.e 
(1)
At the end of the year, 3 boys left the choir, and the ratio of boys to girls became 3:4.
Put y= x from (1), we get
Thus , the number of boys : x= 12
Boys remained in the choir = 12-3=9
