N sweets in a bag. 6 sweets are orange. The rest are yellow. Hannah takes a random sweet from the bag and eats it. She then takes another random sweet from the bag & eats it. The probability Hannah eats 2 orange sweets is 1/3. Show n^2 - n - 90 = 0.

It's a probability equation. The probability of getting an orange sweet the first time is 6/n. The probability of getting an orange sweet the second time is 5/n-1Times those together to get the probability of 2 orange sweets: 6/n x 5/n-1 = 30/n2 - n This we're told equals a 1/3: 1/3 = 30/n2 - n (then times the bottoms up)n2 - n = 90 (take the 90 over to the left)n2 - n - 90 = 0

HB
Answered by Hannah B. Maths tutor

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