What is it? I will help u if I knew what it is.
The problem is to find how many students have either blond hair or glasses and then divide that by the total number of students; that will find the probability.
Since 7 have blonde hair and 9 have glasses, that would be a total of 16 persons if there were no overlap; that is, no blonde wears glasses and nobody who wears glasses is a blonde.
But there are 4 persons who have both blond hair and wears glasses. That means, of the 7 who are blondes, 3 of them do not wear glasses. And, of the 9 who wear glasses, 5 of them are not blondes.
So we have 3 who are blondes without glasses, 5 who wear glasses who are not blondes, and 4 blonds with glasses, for a total of 12 persons.
The probability is, therefore, 12/26 or 6/13.
7-4=3
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FACTORISATION IS BASICALLY FINDING LIKE-TERMS.
1. FIND THE HCF OF 8. HERE, THE HCF IS 8. ALSO, CHECK ALL THE LIKE-TERMS. LIKE-TERMS ARE OUTSIDE THE BRACKET AND UNLIKE TERMS ARE INSIDE.
2. ADD THE TERMS IN THE BRACKET AND THE TERMS OUTSIDE THE BRACKET FROM STEP 1.
8x + 8y + rx + ry
1. 8 (x + y) + r (x + y)
2. (x +y) (8+r)