Question

Ques 1 :- how many multiples of 4 lie between 10 and 250.
Ques 2 :- how many three digit numbers are divisible by 7?

(****don't give irrevalent answer otherwise I will report....
no copy--- paste... explain logically****)​

Answer 1

Step-by-step explanation:

1. Clearly, the numbers between 10 and 250 which are multiple of 4 are 12,16,20,...,248. This is an AP with first term a=12, common difference d=4.

Let there be n terms in this AP, then

a

n

=248⇒a+(n−1)d=248

⇒12+(n−1)×4=248

⇒(n−1)=59

⇒n=60

2.Three Numbers which are divisible by 7 are

105,112,119,.....994

which forms an A.P

first term of this A.P a

1

=105

second term of this A.P is a

2

=112

common difference of this A.P is

d=a

2

−a1=112−105=7

nth term of this A.P is given by

a

n

=a

1

+(n−1)d

⟹a

n

=105+(n−1)7

⟹a

n

=105+7n−7

⟹a

n

=98+7n...….eq(1)

for finding number of terms(n) in this A.P put last term a

n

=994 in eq(1)

⟹994=98+7n

⟹7n=994−98

⟹7n=896

⟹n=

7

896

⟹n=128

hence, their are 128 three digit numbers which are divisible by 7.

Hope this helps mate ☺️.

BORAHAE Army

Answer 2

Where on earth were you (눈‸눈)

ಠಿ_ಠಿ

I missed you. ಠ﹏ಠ

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