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Grade 10Algebra

What is the sum of all no below 400 which are not dividible by 6

13266

66534

79800

93066

Profile image of Amit Tapas
15 Years agoGrade 10
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2 Answers

Profile image of SAGAR SINGH - IIT DELHI
15 Years ago

Dear student,

First of all generate the AP and then take the sum

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Askiitians Expert

Sagar Singh

B.Tech, IIT Delhi

Profile image of Neer Varshney
15 Years ago

Sum of nos. not divisible by 6 and below 400 = {sum of all nos. below 400} - {sum of all nos. divisible by 6 and below 400}

= {1+2+........+399} - {6+12+18+..........+396}

= {399/2[1+399]} - {66/2[6+396]}

= {399*200} - {33*402}

= {79800}-{13226}

= 66574

you can solve this and will get the answer.