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Kanishk Sharma.
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- June 7, 2019 at 1:10 pm #29004
Saptadweepa GangulyParticipantA set of five different positive integers has a mean (average) of 20 and a median of 18. What is the greatest possible integer in the set?
Select one:
a. 35
b. 25
c. 20
d. 60
e. 63How to solve this question ?
What is a median ?
June 7, 2019 at 5:15 pm #29005Srijit MukherjeeParticipantThe total sum of 5 integers is 100 (20 x 5 =100). Also, the middle number (the median) is 18.
Say the numbers are a < b< 18 < c < L, where L is the largest number. Observe that a + b + 18 + c + L = 100.
So, a + b +c + L = 82. Also, the maximum value of L will be when a,b, c are smallest.
So, L will be maximum if a = 1, b =2, and c = 19. i.e. the maximum value of L can be 60.
June 7, 2019 at 9:27 pm #29015AritraModeratori think i have already told you tomorrow in class
July 21, 2020 at 5:41 pm #76605Madhav GargParticipant<p>The positive integers x,yx,y and zz satisfy x×y=14,y×z=10x×y=14,y×z=10 and z×x=35z×x=35</p><p><br />What is the value of x+y+z?</p>
July 23, 2020 at 7:28 am #76671Kanishk SharmaMember<p>@ Madhav</p><p>we know, xy=14 => y=14/x ; zy=1o => z . 14/x =10 =>z/x = 10/14 =5/7</p><p>=> z=5 ; x=7</p><p>substituting the value of x in xy=14,</p><p>we get y=2</p><p>=> x+y+z= 5+2+7 = 14</p>
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