Answer:
Step-by-step explanation:
Since population std deviation is not known, we use t critical value for testing of hypothesis.
a) 90% conf level when n =28
df = 27, t critical = 1.706
b) 95% 28
df =27 and t critical = 2.052
c) 90% and 15
df =14 and t critical = 1.761
d) 95% and n =15
df =14: t critical = 2.145
4 days spending equal amounts so if x is how much he spends per day and y is the original amount then 4x=1/5y bc he has 4/5 left meaning what he spent was 1/5 of the original and after 10 more days which was 14 total he spent all but 30 so the total minus 30 will be how much kyle spent so
14x=y-30 which is y=(14x+30) and substitute that in for y in 4x=1/5y so 4x=1/5 (14x+30)
20x=14x+30
6x=30
x=5 and plug that in either of the original equations 4(5)=1/5y
y=100
so he had $100 and spent $5 per day
Answer:
$1.20
Step-by-step explanation:
A dime is worth 10¢.
10¢ x 12 = 120¢
Since a dollar is 100¢, James would have a dollar and 20¢ left over. So, $1.20.