J = 14
J = 1/2S + 4 1/2
14 = 1/2S + 9/2....multiply everything by 2 to get rid of fractions
28 = S + 9
28 - 9 = S
19 = S
check...
14 = 1/2S + 9/2......S = 19
14 = 1/2(19) + 9/2
14 = 9 1/2 + 9/2
14 = 19/2+ 9/2
14 = 28/2
14 = 14 (correct)
so the sister is 19 <===
Answer:
<em>The answers are for option (a) 0.2070 (b)0.3798 (c) 0.3938
</em>
Step-by-step explanation:
<em>Given:</em>
<em>Here Section 1 students = 20
</em>
<em>
Section 2 students = 30
</em>
<em>
Here there are 15 graded exam papers.
</em>
<em>
(a )Here Pr(10 are from second section) = ²⁰C₅ * ³⁰C₁₀/⁵⁰C₁₅= 0.2070
</em>
<em>
(b) Here if x is the number of students copies of section 2 out of 15 exam papers.
</em>
<em> here the distribution is hyper-geometric one, where N = 50, K = 30 ; n = 15
</em>
<em>Then,
</em>
<em>
Pr( x ≥ 10 ; 15; 30 ; 50) = 0.3798
</em>
<em>
(c) Here we have to find that at least 10 are from the same section that means if x ≥ 10 (at least 10 from section B) or x ≤ 5 (at least 10 from section 1)
</em>
<em>
so,
</em>
<em>
Pr(at least 10 of these are from the same section) = Pr(x ≤ 5 or x ≥ 10 ; 15 ; 30 ; 50) = Pr(x ≤ 5 ; 15 ; 30 ; 50) + Pr(x ≥ 10 ; 15 ; 30 ; 50) = 0.0140 + 0.3798 = 0.3938
</em>
<em>
Note : Here the given distribution is Hyper-geometric distribution
</em>
<em>
where f(x) = kCₓ)(N-K)C(n-x)/ NCK in that way all these above values can be calculated.</em>
Answer:
75 months is 6.25001 calendar years.
Step-by-step explanation:
Answer:
x = 5
Step-by-step explanation:
You want to find x such that ...
x^2 +(x +1)^2 = 61
2x^2 +2x -60 = 0 . . . . . simplify, subtract 61
x^2 +x -30 = 0 . . . . . . . divide by 2
(x +6)(x -5) = 0 . . . . . . . . factor; solutions will make the factors be zero.
The relevant solution is x = 5.
