ECZ 2021 · GCE Paper 2 · Question 2 — Probability
Question from ECZ 2021 · GCE Paper 2 · Question 2
(a) Solve the equation 3x + 5x = 12, giving your answers correct to 2 decimal places.[5]
Verified working — step 1
Clear the fraction: multiply through by x to get 3x2 + 5 = 12x.(b) A boy has a bag containing 5 green balls, 1 red ball and 4 blue balls. A ball is selected at random from the bag and not replaced. A second ball is then selected.
(b(i)) Draw a tree diagram to show all the possible outcomes.[2]
Verified working — step 1
10 balls: 5G, 1R, 4B, drawn WITHOUT replacement.(b(ii)) Find the probability that the two balls are of the same colour.[3]
Verified working — step 1
"Same colour" is GG or BB (RR is impossible with one red):The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.
Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.
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