the letters of the word combine are placed at random in a row in how many ways can an arrangement occur such that all vowels are placed together

Explanation:

The word "combine" has three vowels o, i, and e.

One grouping of the three vowels together leads to oie, which we'll replace with Z for now.

So we have the "word" Zcmbn after taking out the vowels and replacing with Z temporarily. There are 5 letters in Zcmbn making 5! = 5*4*3*2*1 = 120 different permutations.

Within any permutation of Zcmbn, there are 3! = 3*2*1 = 6 ways to arrange the sequence oie

So overall there are 6*120 = 720 different ways to arrange the word "combine" such that all the vowels stick together.

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐

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