Remember distributive property
a(b+c)=ab+ac
we can ervers it
6(31)+6(4)-6(15)=6(31)+6(4)+6(-15)=6(31+4-15)=6(20)=120
The 5 people can seat in a row in 5! ways
But we need to exclude the ways <span>that ann and bob are seated next to each other which is = 4! * 2!
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So, the number of <span>ways can ann, bob, chuck, don and ed be seated in a row such that ann and bob are not seated next to each other = 5! - 4! * 2! = 72
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<span>Another solution:
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<span>If ann seated in one of the ends, the number of ways = 3*2
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<span>If ann didn't seat in one of the ends , the number of ways = 2*3
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So, the total number of <span>ways that can <span>ann, bob be seated = 3*2 + 2*3 = 12
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The remaining persons can seat with a number of ways = 3! = 6
So, the total ways that the five persons can seat = 12*6 = 72
Answer:
B
Step-by-step explanation: divide 520 by 8 and you get 65
