Question

YOU ARE WALKING ALONG A ROW OF TREES NUMBERED FROM 789 TO 954 . HOW MANY TREES WILL YOU FIND MARKED WITH NUMBERS WHICH ARE MULTIPLES OF 8 .

Answer 1

★Answer :-

• 21 Trees

★Solution :-

• So, we can make an Ap of the multiples of 8 between 789 and 954 from the given question

792 , 800 , .........., 952

$\bf{a=792}$

$\bf{d = 800-792=8}$

$\bf{\ a_{n}=952}$

$\sf{\underline{\boxed{\red{\ a_{n}=a+(n-1)d}}}}$

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$\implies\sf{\ a_{n}=a+(n-1)d}$

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$\implies\sf{952=792+(n-1)8}$

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$\implies\sf{952-792=(n-1)8}$

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$\implies\sf{160=(n-1)8}$

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$\implies\sf{(n-1)=\dfrac{160}{8}}$

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$\implies\sf{(n-1)=20}$

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$\implies\sf{n=20+1}$

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$\implies\sf{\boxed{\purple{\dag{n=21\:trees}}}}$

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So , there are 21 trees marked with number which are multiples of 8 between 789 and 954