The average number of visitors of a library in the first 4 days of a week was 58. The average for the 2nd, 3rd, 4th and 5th days was 60.If the number of visitors on the 1st and 5th days were in the ratio 7:8 then what is the number of visitors on the 5th day of the library?

• 64
  
  If number of visitors on 1st, 2nd, 3rd, 4th & 5th day are a, b, c, d & e respectively, then
  a+b+c+d=58*4=232 ----(i) &
  b+c+d+e=60*4=240 ----(ii)
  Subtracting (i) from (ii), e-a=8 ---(iii)
  Given, a/e=7/8 ---(iv)
  So from (iii) & (iv), a=56, e=64
• 10 years agoHelpfull: Yes(18) No(0)
• let assume that 1st day visitors were= 7x
  and, 5th day visitors were= 8x
  so, 7x+ 2nd+3rd+4th=58 *4=232
  and, 2nd+3rd+4th+8x=60*4=240
  
  so, x=8.
  hence answer is 8x=8*8=64.
• 7 years agoHelpfull: Yes(1) No(0)
• Let the number of visitors be K
  Ratio of 1st and 5th day is 7:8
  Number of visitors on 1st and 5th day be 7K and 8K.
  
  Average number of visitors in the first 4 days = 58
  i.e., (M + T + W + TH)/4 = 58
  Then (7K + T + W + TH) = 232
  (7K + T + W + TH) = 232 ...(1)
  
  Average visitors on 2nd, 3rd, 4th and 5th days = 60.
  (T + W + TH + F)/4 = 60
  (T + W + TH + 8K) = 60 x 4 = 240
  (T + W + TH + 8K) = 240 ...(2)
  
  Subtracting (1) from (2) we get,
  8K - 7K = 240 - 232
  K = 8
  
  Therefore visitors on 5th day = 8(8) = 64
  Hence the answer is 64.
• 7 years agoHelpfull: Yes(0) No(0)