Using the t-distribution, it is found that the proportion in a t-distribution less than −1.4 if the samples have sizes n1=30 and n2=40 is of 0.083.
<h3>How to find a proportion in a t-distribution?</h3>
The proportion is found using a calculator, with three inputs:
- The tail of the test, if it is left, right, or two-tailed.
- The amount of degrees of freedom.
In this problem, we have a left-tailed proportion, as we want the proportion that is less than a value, with test statistic t = -1.4 and 30 + 40 - 2 = 68 df, hence the proportion is of 0.083.
More can be learned about the t-distribution at brainly.com/question/16162795
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Sum of aritmetic sqeuqnece is
(n/2)(a1+an)
a1=first term
an=nth term
n=how many terms
so we gots
a1=3(1)-4=-1
a18=50
n=18
(18/2)(-1+50)
(9)(49)
441
other one
a1(1-r^(n+1))/(1-r)
2(1-2^(15+1))/(1-(1/4))
about 2 and 2/3, so closer to 3
Answer:
1/2 or 0.5
Step-by-step explanation:
....
5/8 as a percentage is 62.5
hope i helped :D