Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
junior college 2 | H2 Maths
2 Answers Below
Anyone can contribute an answer, even non-tutors.
Can anyone please help? Very much appreciated.
P(X = x) = k(4⁻ˣ)
When x = 0, we have k(4⁻⁰) = k(1/4⁰) = k(1)
= k
When x = 1, we have k(4⁻¹) = k(1/4¹) = k/4
When x = 2, we have k(4⁻²) = k(1/4²) = k/16
We basically have a geometric series with first term k and common ratio ¼
Since |¼| < 1 , the series converges and we can have a sum to infinity.
Since the total probability is 1, the sum of all these probabilities should add up to 1.
i.e S∞ = 1
Using the formula S∞ = a/(1 - r),
k/(1 - ¼) = 1
k = ¾
See 2 Answers