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Statistics S2 Question Help

Can anyone help with this S2 question? I can do part a and b but don't understand the rest. Thank you :smile:

7. A piece of string AB has length 9 cm. The string is cut at random at a point P and the
random variable X represents the length of the piece of string AP.
(a) Write down the distribution of X.
(1)
(b) Find the probability that the length of the piece of string AP is more than 6 cm.
(1)
The two pieces of string AP and PB are used to form two sides of a rectangle.
The random variable R represents the area of the rectangle.
(c) Show that R = aX2 + bX and state the values of the constants a and b.
(2)
(d) Find E(R).
(6)
(e) Find the probability that R is more than twice the area of a square whose side has the
length of the piece of string AP.
(4)
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you can find answers on physics and maths tutor that's been done not on a mark scheme

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